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1.
BMC Vet Res ; 18(1): 347, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109808

RESUMEN

BACKGROUND: Cottonseed meal (CSM), a relatively rich source of protein and amino acids, is used as an inexpensive alternative to soybean meal (SBM) in poultry diets. However, the toxicity of free gossypol in CSM has been a primary concern. The present study was conducted to investigate the effects of CSM on growth performance, serum biochemical parameters, and liver redox status in goslings at 1 to 28 days of age. Three hundred 1-day-old male goslings were randomly divided into 5 groups (10 goslings/pen, 6 replicate pens/group) and subjected to a 28-day experiment. Five isonitrogenous and isoenergetic diets were formulated such that 0% (control), 25% (CSM25), 50% (CSM50), 75% (CSM75), and 100% (CSM100) of protein from SBM was replaced by protein from CSM. The free gossypol contents in the five diets were 0, 56, 109, 166, and 222 mg/kg, respectively. RESULTS: The results showed that dietary CSM was associated with linear decreases in body weight, average daily feed intake and average daily gain and linear increases in the feed-to-gain ratio from 1 to 28 days of age (P < 0.001). As the dietary CSM concentration increased, a numerical increase was found in the mortality of goslings. According to a single-slope broken-line model, the breakpoints for the average daily gain of dietary free gossypol concentration on days 1 to 14, 15 to 28, and 1 to 28 occurred at 23.63, 14.78, and 18.53 mg/kg, respectively. As the dietary CSM concentration increased, serum albumin (P < 0.001) concentrations decreased linearly and serum uric acid (P = 0.011) increased linearly. The hydroxyl radical scavenging ability (P = 0.002) and catalase (P < 0.001) and glutathione peroxidase (P = 0.001) activities of the liver decreased linearly with increasing dietary CSM. However, dietary CSM did not affect the concentrations of reactive oxygen metabolites, malondialdehyde, or protein carbonyl in the liver. CONCLUSIONS: The increasing dietary CSM increased the concentration of free gossypol and altered the composition of some amino acids in the diet. A high concentration of CSM reduced the growth performance of goslings aged 1 to 28 days by decreasing feed intake, liver metabolism, and antioxidant capacity. From the primary concern of free gossypol in CSM, the tolerance of goslings to free gossypol from CSM is low, and the toxicity of free gossypol has a cumulative effect over time.


Asunto(s)
Aceite de Semillas de Algodón , Gosipol , Aminoácidos/metabolismo , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Catalasa , Aceite de Semillas de Algodón/análisis , Aceite de Semillas de Algodón/metabolismo , Aceite de Semillas de Algodón/farmacología , Gansos/metabolismo , Glutatión Peroxidasa , Gosipol/análisis , Gosipol/metabolismo , Gosipol/farmacología , Radical Hidroxilo/análisis , Radical Hidroxilo/metabolismo , Radical Hidroxilo/farmacología , Hígado/metabolismo , Masculino , Malondialdehído/metabolismo , Oxidación-Reducción , Oxígeno/metabolismo , Albúmina Sérica/análisis , Glycine max/metabolismo , Ácido Úrico/análisis
2.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806141

RESUMEN

The study of antioxidants and their implications in various fields, from food engineering to medicine and pharmacy, is of major interest to the scientific community. The present paper is a critical presentation of the most important tests used to determine the antioxidant activity, detection mechanism, applicability, advantages and disadvantages of these methods. Out of the tests based on the transfer of a hydrogen atom, the following were presented: the Oxygen Radical Absorption Capacity (ORAC) test, the Hydroxyl Radical Antioxidant Capacity (HORAC) test, the Total Peroxyl Radical Trapping Antioxidant Parameter (TRAP) test, and the Total Oxyradical Scavenging Capacity (TOSC) test. The tests based on the transfer of one electron include the Cupric Reducing Antioxidant Power (CUPRAC) test, the Ferric Reducing Antioxidant Power (FRAP) test, the Folin-Ciocalteu test. Mixed tests, including the transfer of both a hydrogen atom and an electron, include the 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) test, and the [2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl] (DPPH) test. All these assays are based on chemical reactions and assessing the kinetics or reaching the equilibrium state relies on spectrophotometry, presupposing the occurrence of characteristic colours or the discolouration of the solutions to be analysed, which are processes monitored by specific wavelength adsorption. These assays were successfully applied in antioxidant analysis or the determination of the antioxidant capacity of complex samples. As a complementary method in such studies, one may use methods based on electrochemical (bio)sensors, requiring stages of calibration and validation. The use of chemical methods together with electrochemical methods may result in clarification of the operating mechanisms and kinetics of the processes involving several antioxidants.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/análisis , Depuradores de Radicales Libres/farmacología , Radical Hidroxilo/farmacología , Animales , Benzotiazoles/química , Bioensayo/métodos , Compuestos de Bifenilo , Técnicas Electroquímicas , Humanos , Hidrógeno/química , Cinética , Oxígeno/química , Fenoles/análisis , Picratos , Especies Reactivas de Oxígeno/metabolismo , Ácidos Sulfónicos/química , Superóxido Dismutasa/metabolismo
3.
J Phys Chem B ; 121(25): 6139-6147, 2017 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-28574710

RESUMEN

The propensity of 5-selenocyanatouracil (SeCNU) to decomposition induced by attachment of electron was scrutinized with the G3B3 composite quantum-chemical method and radiolytic studies. Favorable thermodynamic (Gibbs free reaction energy of -13.65 kcal/mol) and kinetic (Gibbs free activation energy of 1.22 kcal/mol) characteristics revealed by the G3B3 free energy profile suggest SeCNU to be sensitive to electron attachment. The title compound was synthesized in the reaction between uracil and selenocyanogen chloride in acetic acid. Then, an aqueous and deoxygenated solution of the HPLC purified compound containing tert-butanol as a hydroxyl radical scavenger was irradiated with X-rays. SeCNU radio-degradation results in two major products: the U-Se-Se-U dimer and the adduct of the ●OtBu radical to the U-Se● radical, U-Se-OtBu. The effects of radiolysis as well as the results of G3B3 calculations point to U-Se● as the primary product of dissociative electron attachment to SeCNU. The MTT test shows that SeCNU is nontoxic in vitro in concentrations equal to or lower than 10-6 M. Ionizing radiation will probably induce cytotoxic intra- and interstrand DNA cross-links as well as protein-DNA cross-links in the genomic DNA labeled with SeCNU.


Asunto(s)
Electrones , Radical Hidroxilo/química , Selenio/química , Uracilo/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Radical Hidroxilo/síntesis química , Radical Hidroxilo/farmacología , Células MCF-7 , Estructura Molecular , Teoría Cuántica , Selenio/farmacología , Termodinámica , Uracilo/química , Rayos X
4.
J Microbiol Biotechnol ; 24(9): 1232-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25022524

RESUMEN

Lycopene, which is a well-known red carotenoid pigment, has been drawing scientific interest because of its potential biological functions. The current study reports that lycopene acts as a bactericidal agent by inducing reactive oxygen species (ROS)-mediated DNA damage in Escherichia coli. Lycopene treatment elevated the level of ROS-in particular, hydroxyl radicals ((•)OH) -which can damage DNA in E. coli. Lycopene-induced DNA damage in bacteria was confirmed and we also observed cell filamentation caused by cell division arrest, an indirect marker of the DNA damage repair system, in lycopene-treated E. coli. Increased RecA expression was observed, indicating activation of the DNA repair system (SOS response). To summarize, lycopene exerts its antibacterial effects by inducing (•)OH -mediated DNA damage that cannot be ameliorated by the SOS response. Lycopene may be a clinically useful adjuvant for current antimicrobial therapies.


Asunto(s)
Carotenoides/metabolismo , Daño del ADN/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Radical Hidroxilo/farmacología , Estrés Oxidativo/efectos de los fármacos , Antibacterianos , Puntos de Control del Ciclo Celular/efectos de los fármacos , ADN Bacteriano/análisis , ADN Bacteriano/química , Escherichia coli/genética , Radical Hidroxilo/metabolismo , Etiquetado Corte-Fin in Situ , Licopeno , Respuesta SOS en Genética/efectos de los fármacos
5.
J Food Sci ; 77(11): C1131-5, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23057510

RESUMEN

UNLABELLED: Ripe and unripe exotic pepino fruit were evaluated for antioxidant activity, total phenols, and flavonoid content. The antioxidant potency was investigated by employing various established in vitro systems, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2-2'-azinobis(3-ethylbenthiazoline-6-sulphonic acid (ABTS), hydroxyl radical scavenging, reducing power, ferrous ion chelation, ferric reducing antioxidant power (FRAP), and lipid peroxidation. The EC(50) values of ripe ethanolic extract on DPPH radical, reducing power, ferrous ion chelation, ABTS radical, FRAP, hydroxyl radical, lipid peroxidation (brain), and lipid peroxidation (liver) were obtained to be 2.20, 2.81, <5.00, 34.06, 8.53, 1.30, 1.75, and 0.51 mg/mL, respectively. However, the EC(50) values for unripe fruit extract were noted to be 3.75, 3.40, 11.25, 40.12, 9.75, 0.80, 1.91, and 0.63 mg/mL, respectively. Ripe fruit exhibited the highest values of antioxidant activity in all the scavenging assays except for hydroxyl radical scavenging assay. Ripe pepino had higher total phenol and flavonoid content than unripe fruit. This study suggests that possible mechanism of the biological activities may be due to free radical scavenging and antioxidant characteristics, which may be due to the presence of polyphenols in the fruit extracts. PRACTICAL APPLICATION: The ripe and unripe pepino fruit have excellent antioxidant properties, so the results obtained in this study clearly indicate that pepino fruit has a significant potential to use as a natural antioxidant agent and possibly as a food supplement.


Asunto(s)
Antioxidantes/análisis , Frutas/química , Extractos Vegetales/análisis , Solanum/química , Animales , Antioxidantes/farmacología , Benzotiazoles/análisis , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Flavonoides/análisis , Flavonoides/farmacología , Radical Hidroxilo/análisis , Radical Hidroxilo/farmacología , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Extractos Vegetales/farmacología , Polifenoles/análisis , Polifenoles/farmacología , Ratas , Ácidos Sulfónicos/análisis
6.
Immunopharmacol Immunotoxicol ; 34(4): 661-6, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22239430

RESUMEN

Phenolic composition and antioxidant activities of the aqueous extract of Arisaema cum Bile, which is widely used as a folk medicine in Korea, were determined. Phenolic composition profile revealed that the aqueous extract is rich in sinapic acid (13.14 mg/100 g extract), catechin (9.88 mg/100 g extract), neohesperidin (7.38 mg/100 g extract), and chlorogenic acid (3.64 mg/100 g extract). The aqueous extract effectively scavenged toward 2,2-diphenyl-1-picrylhydrazyl (90.63%), hydrogen peroxide (98.13%), and hydroxyl radical (59.62%) at 2.0 mg/mL, and also showed high reducing power. In cytotoxic evaluation, the aqueous extract exhibited no significant cytotoxicity in human fibroblast, and it also exhibited appreciable suppression of intracellular reactive oxygen species and inhibition of lipid peroxidation. In addition, the aqueous extract upregulated the level of glutathione in a dose-dependent manner. Taken together, the aqueous extract of Arisaema cum Bile could be considered as a potential natural source that may be useful for curing diseases arising from oxidative deterioration.


Asunto(s)
Antioxidantes , Arisaema/química , Mezclas Complejas , Fibroblastos/inmunología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Compuestos de Bifenilo/farmacología , Línea Celular , Mezclas Complejas/química , Mezclas Complejas/farmacología , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacología , Relación Dosis-Respuesta a Droga , Fibroblastos/metabolismo , Humanos , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/farmacología , Oxidación-Reducción/efectos de los fármacos , Picratos/farmacología
7.
J Med Food ; 14(10): 1159-66, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21548805

RESUMEN

Herbal drugs have been used since ancient times to treat a wide range of diseases. Morinda citrifolia Linn (popularly known as "Noni") has been used in folk medicine by Polynesians for over 2,000 years. It is reported to have a broad range of therapeutic effects, including effects against headache, fever, arthritis, gingivitis, respiratory disorders, infections, tuberculosis, and diabetes. The aim of this study was to investigate the antioxidant, anti-inflammatory, antinociceptive, and antibacterial properties of the aqueous extract from M. citrifolia leaves (AEMC). Antioxidant activity was observed against lipid peroxidation, nitric oxide, and hydroxyl radicals. The antinociceptive effect of AEMC was observed in the acetic acid-induced writhing test at the higher dose. Moreover, AEMC significantly reduced the leukocyte migration in doses of 200 and 400 mg/kg and showed mild antibacterial activity. Together, the results suggest that properties of M. citrifolia leaf extract should be explored further in order to achieve newer tools for managing painful and inflammation conditions, including those related to oxidant states.


Asunto(s)
Analgésicos/farmacología , Antioxidantes/farmacología , Movimiento Celular/efectos de los fármacos , Leucocitos/efectos de los fármacos , Morinda/química , Extractos Vegetales/farmacología , Animales , Antibacterianos/farmacología , Antiinflamatorios/farmacología , Cromatografía Líquida de Alta Presión , Radical Hidroxilo/farmacología , Leucocitos/citología , Peroxidación de Lípido/efectos de los fármacos , Masculino , Medicina Tradicional , Ratones , Óxido Nítrico/análisis , Óxido Nítrico/metabolismo , Fenol/farmacología , Hojas de la Planta/química , Tiobarbitúricos/análisis , Tiobarbitúricos/metabolismo
8.
J Mol Graph Model ; 29(6): 784-94, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21334935

RESUMEN

Two species of Thai medicinal plants, Dalbergia parviflora R. (Leguminosae) and Belamcanda chinensis L. (Iridaceae), used traditionally for the regulation of menstrual disorders, have been found to contain a large number of potential estrogen-like compounds. A set of some 55 isolated isoflavonoids and diphenolics showed a wide range of estrogen activity as determined in breast cancer MCF-7 and T47D cell proliferation assays. This set of compounds was studied by means of computational techniques including quantitative structure-activity relationships (QSAR) and molecular modeling. It was found that the estrogenic potencies of the studied compounds depend mainly upon the presence/absence of hydroxyl groups attached to 3' and 5' positions of B ring of the isoflavone scaffold and the inter-atomic distance between the hydroxyl groups attached to the outer terminal positions 7 of A ring and 4' of B ring. In a QSAR model employing ligand-receptor interaction energy descriptors, the LigScore scoring function of Cerius(2) virtual screening module, which describes the receptor affinities of simultaneous binding to estrogenic receptors α and ß (ER(α) and ER(ß)), led to the best correlation between the observed estrogenic activities and computed descriptors. Consideration of independent binding to ER(α) and ER(ß) did not result in statistically significant QSAR models. It was thus concluded that simultaneous and possibly competitive interaction of the compounds with the ER(α) and ER(ß) receptors, in which the presence of hydroxyl groups at the abovementioned positions of the isoflavonoids and diphenolics molecular scaffold plays a dominant role, may determine the estrogenic potency of the considered phytochemicals.


Asunto(s)
Compuestos de Bifenilo/química , Dalbergia/química , Flavonoides/química , Iridaceae/química , Isoflavonas/química , Fitoestrógenos/química , Plantas Medicinales/química , Relación Estructura-Actividad Cuantitativa , Compuestos de Bifenilo/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Flavonoides/metabolismo , Humanos , Radical Hidroxilo/química , Radical Hidroxilo/farmacología , Isoflavonas/metabolismo , Modelos Moleculares , Fitoestrógenos/metabolismo , Fitoestrógenos/farmacología , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Receptores de Estrógenos/química , Receptores de Estrógenos/metabolismo , Tailandia
9.
Bioorg Med Chem ; 18(17): 6538-46, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20692173

RESUMEN

The reported ribonuclease A inhibitory activity of the green tea extracts prompted us to synthesize novel catechin/epicatechin based conjugates with resorcinol and phloroglucinol with the aim to increase the number of phenolic OH groups. These are found to be more effective inhibitors of ribonuclease A as compared to catechin and epicatechin thus indicating the importance of number of phenolic OH groups for the inhibition of ribonucleolytic activity. Fluorescence studies have been carried out to evaluate the binding parameters. The protein-ligand docking studies are also performed to gain insight into the protein-polyphenols interactions. The epicatechin based polyphenols 1 and 2 also showed inhibition of angiogenin-induced angiogenesis, as determined by chorioallantoic membrane (CAM) assay.


Asunto(s)
Catequina/análogos & derivados , Floroglucinol/análogos & derivados , Resorcinoles/farmacología , Ribonucleasa Pancreática/antagonistas & inhibidores , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacología , Animales , Catequina/química , Catequina/farmacología , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Humanos , Radical Hidroxilo/química , Radical Hidroxilo/farmacología , Modelos Moleculares , Neovascularización Fisiológica/efectos de los fármacos , Floroglucinol/química , Floroglucinol/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Resorcinoles/química , Ribonucleasa Pancreática/metabolismo , Té/química
10.
Free Radic Biol Med ; 49(5): 881-93, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20600839

RESUMEN

Abnormal proliferation of vascular smooth muscle cells (VSMCs) plays an important role in the development of cardiovascular diseases. PMC (2,2,5,7,8-pentamethyl-6-hydroxychromane) is the most potent hydrophilic derivative of vitamin E. In this study, we investigated the mechanisms of PMC inhibition of VSMC proliferation in vitro and in vivo. PMC (20 and 50 microM) obviously suppressed proliferation of PDGF-BB-stimulated cells, but not resting cells, and arrested cell cycle progression at the G(2)/M phase. A significant reduction in neointimal formation in carotid arteries was observed in PMC (5mg/kg/day)-treated rats after balloon angioplasty. Activation of STAT3, JAK2, PLCgamma1, PKCdelta, and ROS, but not ERK1/2, AKT, or PKCalpha, was markedly inhibited by PMC in PDGF-BB-stimulated VSMCs. Deferoxamine and PMC significantly inhibited the phosphorylation of PLCgamma1 and JAK2 and arrested cell cycle progression at the G(2)/M phase. These events, however, were reversed in the presence of Fe(2+). Moreover, PMC directly inhibited hydroxyl radical formation in both the Fenton reaction and VSMCs according to an electron spin resonance study. In conclusion, this study demonstrates for the first time that PMC inhibits VSMC proliferation in vitro and balloon injury-induced neointimal formation in vivo. The inhibitory mechanism of PMC may involved the inhibition of hydroxyl radical-mediated PLCgamma1-PKCdelta and JAK2-STAT3 activation and causes cell cycle arrest at the G(2)/M phase. PMC treatment may represent a novel approach for lowering the risk of or improving function in abnormal VSMC proliferation-related vascular diseases.


Asunto(s)
Benzopiranos/farmacología , Proliferación Celular/efectos de los fármacos , Radical Hidroxilo/farmacología , Janus Quinasa 2/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Fosfolipasa C gamma/metabolismo , Animales , Antioxidantes/farmacología , Ciclo Celular/efectos de los fármacos , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Masculino , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/fisiología , Fosforilación/efectos de los fármacos , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Vitamina E/análogos & derivados , Vitamina E/farmacología
11.
Xenobiotica ; 40(5): 319-30, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20230191

RESUMEN

An investigation into the post-translational activation of cDNA-expressed human phenylalanine 4-monooxygenase and human hepatic cytosolic fraction phenylalanine 4-monooxygenase activity with respect to both endobiotic metabolism and xenobiotic metabolism revealed that the reactive oxygen species (hydrogen peroxide and hydroxyl radical) and reactive nitrogen species (nitric oxide and peroxynitrite) could elicit the post-translational activation of the enzyme with respect to both of these biotransformation reactions. In virtually all instances, the K(m) values were decreased and the V(max) values were increased; the only exceptions observed being with hydrogen peroxide and L-phenylalanine. These effects were shown to occur at activator concentrations known to exist in physiological situations and, hence, suggest that reactive oxygen and reactive nitrogen species may cause, and may be involved with, the post-translational activation of phenylalanine 4-monooxygenase within the human body. This mechanism, in response to free-radical bursts, may enable the enzyme to expand its substrate range and to process certain xenobiotics as and when required.


Asunto(s)
Fenilalanina Hidroxilasa/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Especies de Nitrógeno Reactivo/farmacología , Especies Reactivas de Oxígeno/farmacología , Xenobióticos/metabolismo , Carbocisteína/metabolismo , Citosol/efectos de los fármacos , Citosol/enzimología , ADN Complementario/genética , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/farmacología , Hígado/efectos de los fármacos , Hígado/enzimología , Óxido Nítrico/farmacología , Ácido Peroxinitroso/farmacología , S-Nitrosoglutatión/farmacología
12.
Redox Rep ; 15(6): 234-42, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21208522

RESUMEN

The antioxidant activities of the extract and its relevant fraction as well as isolated compounds from the dead bark of Araucaria angustifolia are presented. This tree represents the Mixed Ombrophile Forest, which is endangered due to extensive logging. The dead bark of Araucaria is naturally discarded by the tree, and its hydroalcoholic crude extract has exhibited protective qualities against stress induced by H(2)O(2) in cell culture. Using several in vitro models, here we describe the antioxidant potential of the crude extract and its component ethyl acetate fraction and also of some compounds isolated from the ethyl acetate fraction. We provide the first description of the isolation of two natural product afzelechin derivatives. The extract and isolated compounds, particularly epiafzelechin protocatechuate (5), displayed very high antioxidant activity, as did compound 4, quercetin, which is well known for its antioxidant properties. In a DPPH assay, compound 5 exhibited an IC(50) of 0.7 µM; in a lipid peroxidation assay; IC(50) values of 21 µM and 35 µM were obtained when the oxidation was induced by UV and ascorbate free radicals, respectively.


Asunto(s)
Antioxidantes/química , Corteza de la Planta/química , Extractos Vegetales/química , Tracheophyta/química , Ácido Deshidroascórbico/análogos & derivados , Ácido Deshidroascórbico/farmacología , Radical Hidroxilo/farmacología , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/efectos de la radiación , Estructura Molecular , Oxidación-Reducción/efectos de los fármacos , Rayos Ultravioleta
13.
J Med Food ; 10(3): 401-7, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17887932

RESUMEN

Bullfrog (Rana catesbeiana Shaw) muscle protein was enzymatically hydrolyzed for extraction of an antioxidant peptide. Antioxidant peptide from bullfrog muscle protein hydrolysate (APBMH) was purified using consecutive chromatographic methods, and the amino acid sequence was identified as being Leu-Glu-Gln-Gln-Val-Asp-Asp-Leu-Glu-Gly-Ser-Leu-Glu-Gln-Glu-Lys-Lys (molecular mass of 1,988 Da) by quantitative time-of-flight electrospray ionization mass spectroscopy. To assess antioxidant activities of APBMH, two different in vitro systems were employed: free radical scavenging activity by electron spin resonance (ESR) spectroscopy and polyunsaturated fatty acid (PUFA) peroxidation inhibition assay. ESR revealed that APBMH is an effective free radial scavenger with activity similar to that of vitamin C against 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, and superoxide radicals, and its 50% inhibitory concentration values were 179.4 microM, 162.7 microM, and 176.1 microM, respectively. APBMH also significantly retarded PUFA oxidation, and more potently than did alpha-tocopherol, which was used as a positive control. In addition, the ability of APBMH to inhibit the oxidative damage of DNA was assessed, in vitro, by measuring the conversion of supercoiled pBR322 plasmid DNA to the open circular form. It was found that APBMH significantly protected hydroxyl radical-induced DNA damage dose-dependently.


Asunto(s)
Antioxidantes/aislamiento & purificación , Proteínas Musculares/química , Péptidos/aislamiento & purificación , Rana catesbeiana , Secuencia de Aminoácidos , Animales , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Daño del ADN/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Hidrólisis , Radical Hidroxilo/farmacología , Peroxidación de Lípido/efectos de los fármacos , Péptido Hidrolasas/metabolismo , Péptidos/química , Péptidos/farmacología , Espectrometría de Masa por Ionización de Electrospray
14.
J Nat Prod ; 69(10): 1399-403, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17067150

RESUMEN

Six new phenylethanoid glucosides, ternstrosides A-F (1-6), a new kaempferol derivative (7), and eight known compounds were isolated from the fresh leaves of Ternstroemia japonica. The structures were elucidated by 1D and 2D NMR spectroscopic analyses. Compounds 1-7 showed potent antioxidative activity in three different tests, with IC50 values in the range 3.26-6.50 microM in the hydroxyl radical (*OH) inhibitory activity test, 33.29-82.21 microM in the total ROS (reactive oxygen species) inhibitory activity test, and 1.14-13.53 microM in the peroxynitrite (ONOO-) scavenging activity test.


Asunto(s)
Antioxidantes , Ericaceae/química , Glucósidos , Fenoles , Plantas Medicinales/química , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Depuradores de Radicales Libres/farmacología , Glucósidos/química , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Radical Hidroxilo/farmacología , Concentración 50 Inhibidora , Riñón/citología , Corea (Geográfico) , Masculino , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Ácido Peroxinitroso/farmacología , Fenoles/química , Fenoles/aislamiento & purificación , Fenoles/farmacología , Hojas de la Planta/química , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/farmacología
15.
J Med Food ; 8(3): 299-304, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16176138

RESUMEN

The antioxidative capacity of two lactic acid bacteria isolated from Kimchi, a Korean fermented food, was evaluated by measuring the resistance to reactive oxygen species (ROS) and compared with that of Lactobacillus rhamnosus GG as a positive control. Both intact cells and cell-free extracts of Lactobacillus plantarum KCTC 3099 exhibited higher antioxidative activity in inhibiting lipid peroxidation among the strains evaluated with an inhibitory level of 38.6% and 48.5%, respectively. To evaluate the resistance of the two lactic acid bacteria to ROS, we tested their survival in the presence of 1 mM hydrogen peroxide, 0.4 mM hydroxyl radicals, and superoxide anions induced by 10 mM paraquat. L. plantarum KCTC 3099 was viable even after 8 hours in the presence of both 1 mM hydrogen peroxide and 0.4 mM hydroxyl radicals. Moreover, the survival of L. plantarum KCTC 3099 was not affected by superoxide anions generated by using paraquat, indicating that it has resistance to superoxide anions. To define the antioxidative mechanism, superoxide dismutase (SOD) and metal ion chelating activities were determined. L. plantarum KCTC 3099 presented little SOD activity, but had the higher level of chelating activity for both Fe2+ and Cu2+ metal ions at 13.6 ppm and 23.9 ppm, respectively. These results suggested that the antioxidative capacity of L. plantarum KCTC 3099 is apparently caused by chelating metal ions rather than by SOD activation.


Asunto(s)
Fermentación , Microbiología de Alimentos , Lactobacillus plantarum/metabolismo , Estrés Oxidativo , Antioxidantes/análisis , Antioxidantes/metabolismo , Sistema Libre de Células/enzimología , Quelantes , Cobre/química , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/farmacología , Quelantes del Hierro/análisis , Quelantes del Hierro/química , Lactobacillus plantarum/química , Lactobacillus plantarum/efectos de los fármacos , Ácido Linoleico/química , Oxidación-Reducción , Paraquat/farmacología , Especies Reactivas de Oxígeno/farmacología , Superóxido Dismutasa/metabolismo , Superóxidos/farmacología
16.
J Agric Food Chem ; 52(13): 4270-3, 2004 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15212479

RESUMEN

Commercial pectins with different degrees of esterification (DE) were reacted with equal volumes of 2 M alkaline hydroxylamine (pH 12.0) at room temperature for 4 h to prepare pectin hydroxamic acids (PHAs; DE94T4, DE65T4, and DE25T4) according to a previously reported method (Hou et al., J. Agric. Food Chem. 2003, 51, 6362-6366) and were used to test the antioxidant and antiradical activities in comparison with those of DE94, DE65, and DE25 pectins. The half-inhibition concentrations, IC(50), of scavenging activity against DPPH were 1.51, 5.43, and 5.63 mg/mL for DE94T4, DE65T4, and DE25T4, respectively, and were much lower than those of corresponding DE pectins under the same concentrations. The scavenging activities of PHAs for DPPH radicals were positively correlated with original DE values of pectin. The optimal pH of DE94T4 for scavenging DPPH radicals was 7.9 or 8.0. Using electron spin resonance (ESR) for scavenging hydroxyl radicals, under the same concentrations of 125 microg/mL, DE94T4, DE65T4, and DE25T4, respectively, exhibited 73.53, 69.01, and 55.17% antiradical activities. PHAs also exhibited protection against hydroxyl radical-mediated DNA damage and anti-human low-density lipoprotein peroxidation tests.


Asunto(s)
Antioxidantes/farmacología , Ácidos Hidroxámicos/farmacología , Pectinas/química , Animales , Compuestos de Bifenilo , Bovinos , Cobre/farmacología , Daño del ADN/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Depuradores de Radicales Libres , Humanos , Radical Hidroxilo/farmacología , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/química , Picratos/química
17.
Mech Ageing Dev ; 124(8-9): 977-83, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14499503

RESUMEN

In this study, the effect of EGb 761, a standard extract of Ginkgo biloba leaf, on thymocyte apoptosis and age-related thymic atrophy and on peripheral immune dysfunctions was investigated in mice. When primary culture of thymocytes was preincubated with 100 microg/ml EGb 761 before their exposure to hydroxyl radicals (*OH) generated by Fe(2+)-mediated Fenton reaction, apoptotic cell death induced by *OH was distinctly prevented as determined by DNA laddering, the TUNEL assay and flow cytometric analysis. Furthermore, oral EGb 761 administration (about 1.5 mg/day/mouse) for 60 consecutive days led to a significant thymic regrowth in 22-month-old mice as revealed by the increment of thymus weight and total numbers of thymocytes. Partial recovery of peripheral immune capacities such as mitogen responsiveness and NK cell activity were also found in the old mice after 60 days of EGb 761 supplementation. Taken together, our study indicates that in addition to its protective and rescuing abilities on neurodegenerative disorders and cardiovascular diseases, EGb 761 was also found active in the rejuvenation of degenerated thymus and accordingly the strengthening of the immune system. These beneficial effects of EGb 761 on immune system are based on its antioxidant properties as well as the cell proliferation-stimulating effect.


Asunto(s)
Envejecimiento , Apoptosis , Radical Hidroxilo/farmacología , Enfermedades del Sistema Inmune/fisiopatología , Extractos Vegetales/farmacología , Timo/patología , Timo/fisiopatología , Animales , Atrofia , Células Cultivadas , Femenino , Ginkgo biloba , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/fisiopatología , Ratones , Ratones Endogámicos C57BL , Recuperación de la Función , Timo/efectos de los fármacos
18.
J Agric Food Chem ; 51(15): 4389-93, 2003 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-12848515

RESUMEN

The potato (Solanum tuberosum L.) tuber storage protein, patatin, was purified to homogeneity with a molecular mass of 45 kDa. The purified patatin showed antioxidant or antiradical activity by a series of in vitro tests, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (half-inhibition concentration, IC(50), was 0.582 mg/mL) scavenging activity assays, anti-human low-density lipoprotein peroxidation tests, and protections against hydroxyl radical-mediated DNA damages and peroxynitrite-mediated dihydrorhodamine 123 oxidations. Using electron paramagnetic resonance (EPR) spectrometry for hydroxyl radical detections, it was found that the intensities of the EPR signal were decreased by the increased amounts of patatin added (IC(50) was 0.775 mg/mL). Through modifications of patatin by iodoacetamide or N-bromosuccinimide, it was found that the antiradical activities of modified patatin against DPPH or hydroxyl radicals were decreased. It was suggested that cysteine and tryptophan residues in patatin might contribute to its antioxidant activities against radicals.


Asunto(s)
Antioxidantes/farmacología , Hidrolasas de Éster Carboxílico/farmacología , Proteínas de Plantas/farmacología , Solanum tuberosum/química , Animales , Compuestos de Bifenilo , Hidrolasas de Éster Carboxílico/aislamiento & purificación , Bovinos , Cobre/farmacología , Daño del ADN/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Depuradores de Radicales Libres/farmacología , Humanos , Radical Hidroxilo/análisis , Radical Hidroxilo/química , Radical Hidroxilo/farmacología , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/química , Picratos/química , Proteínas de Plantas/aislamiento & purificación , Timo/química
19.
J Agric Food Chem ; 51(5): 1506-12, 2003 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-12590506

RESUMEN

Lactuca indica (Compositae) is an edible wild vegetable, used as a folk medicine in anti-inflammatory, antibacterial, and other medications in Asia. This is the first scientific evaluation of the chemopreventive therapeutic properties of L. indica using five antioxidation assay systems. An extract from L. indica was found to possess significant free radical scavenging activity, effectively protecting phix174 supercoiled DNA against strand cleavage and reducing oxidative stress in human promyelocytic leukemia HL-60 cells. Moreover, extracts of L. indica almost totally inhibited nitric oxide production and the mRNA expression of inducible nitric oxide synthase, at a dosage of 100 microg/mL, in LPS-stimulated macrophage RAW264.7 cells. Bioactivity-guided chromatographic fractionation and metabolite profiling coupled with spectroscopic analyses revealed that the six phenolic compounds, that is, protocatechulic acid (1), methyl p-hydroxybenzoate (2), caffeic acid (3), 3,5-dicaffeoylquinic acid (4), luteolin 7-O-beta-glucopyranoside (5), and quercetin 3-O-beta-glucopyranoside (6), are the major antioxidative constituents in the L. indica extract.


Asunto(s)
Antioxidantes/análisis , Lactuca/química , Extractos Vegetales/análisis , Antioxidantes/farmacología , Línea Celular , Cromatografía Líquida de Alta Presión , Daño del ADN/efectos de los fármacos , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/farmacología , Expresión Génica/efectos de los fármacos , Células HL-60 , Humanos , Radical Hidroxilo/farmacología , Macrófagos/enzimología , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Estrés Oxidativo/efectos de los fármacos , Fenoles/análisis , Fenoles/farmacología , Extractos Vegetales/farmacología , ARN Mensajero/análisis , Superóxidos/química
20.
Exp Lung Res ; 28(2): 99-121, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11868826

RESUMEN

Free radicals (FRs) and serum proteins have both been implicated in the pathophysiology of surfactant dysfunction during acute lung injury (ALI). This study examines how these 2 distinct mechanisms interact to contribute to altered surfactant function in this setting. Calf lung surfactant (2 mg/mL) was incubated with no additives (C = control), and with low = (LD = 125 microM FeCl2; 250 microM H2O2) and high-dose (HD = 250 microM FeCl2, 500 microM H2O2) Fenton reaction reagents to generate hydroxyl radical. Each condition was studied with (1) no protein (N); and with 25%, 200%, and 800% (weight protein/weight phospholipid) protein added as (2) bovine albumin, (3) bovine fibrinogen, (4) hemoglobin, or (5) calf serum. Lipid (LFR) and protein (PFR) free-radical products, and modifications in the tertiary structure of Surfactant Protein A (SPA) on Western blot, were observed in N LD and N HD samples. Added proteins reduced LFR and PFR changes as well as SPA structural changes. Protection was greatest for fibrinogen, hemoglobin, and serum, and least for albumin. Minimal to no dysfunction, assayed by pulsating surfactometry, was observed in all samples. These findings indicate that addition of serum proteins to surfactant at 2 mg/mL protects against, rather than promotes, FR-mediated chemical changes in surfactant lipid and protein constituents.


Asunto(s)
Proteínas Sanguíneas/farmacología , Pulmón/metabolismo , Proteolípidos/metabolismo , Surfactantes Pulmonares/metabolismo , Animales , Western Blotting , Bovinos , Sinergismo Farmacológico , Fibrinógeno/farmacología , Radicales Libres/metabolismo , Radicales Libres/farmacología , Hemoglobinas/farmacología , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/metabolismo , Radical Hidroxilo/farmacología , Técnicas In Vitro , Hierro/farmacología , Proteínas Asociadas a Surfactante Pulmonar , Síndrome de Dificultad Respiratoria/metabolismo , Albúmina Sérica/farmacología , Tensión Superficial/efectos de los fármacos , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
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