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1.
Food Chem ; 305: 125437, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499290

RESUMO

Total polyphenols and flavonoids content, phenolics profile by HPLC, and antioxidant activity of ten fruit beer produced adding fruits during the fermentation process were analyzed. The fruits were: cherry, raspberry, peach, apricot, grape, plum, orange and apple. Antioxidant activity, total polyphenols and flavonoids content were considerably higher in most of the fruit beers in respect to conventional, no-fruit beers. Cherries beers exhibit the highest values, followed by grape, plum and orange beers. An enrichment was observed in catechin and quercetin content in all fruit beers examined. Myricetin and resveratrol were also detected in most of the fruit beers. Among phenolic acids, an enrichment in chlorogenic, neochlorogenic, p-coumaric and caffeic acids was measured in most of the fruit beers in respect to conventional beers. Our findings show that fruits addition during the fermentation process considerably increased the antioxidant activity of beer and qualitatively and quantitatively improved its phenolics profile.

2.
Foods ; 7(3)2018 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-29522434

RESUMO

Polyphenols content and antioxidant activity are directly related to the quality of wine. Wine also contains sulfites, which are added during the winemaking process. The present study aimed to evaluate the effects of sulfites on the assays commonly used to measure the antioxidant activity and polyphenols and flavonoids content of white wines. The effects of sulfites were explored both in the standard assays and in white wine. The addition of sulfites (at 1-10 µg) in the standard assays resulted in a significant, positive interference in the Folin-Ciocalteu's assay used for polyphenols measurements and in both the Ferric Reducing Antioxidant Power and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation decolorization assays, which were used for antioxidant activity evaluation. A negative interference of sulfites (at 1-20 µg) was observed for the colorimetric aluminium-chloride flavonoids assay. The addition of sulfites to organic white wines (at 25-200 mg/L wine) clearly resulted in a significant overestimation of antioxidant activity and polyphenols content, and in an underestimation of flavonoids concentration. To overcome sulfite interferences, white wines were treated with cross-linked polyvinylpyrrolidone. The total polyphenols content and antioxidant activity measurements obtained after polyvinylpyrrolidone treatment were significantly lower than those obtained in the untreated wines. Flavonoids were expected to be higher after polyvinylpyrrolidone treatment, but were instead found to be lower than for untreated wines, suggesting that in addition to sulfites, other non-phenolic reducing compounds were present in white wine and interfered with the flavonoid assay. In view of our results, we advise that a purification procedure should be applied in order to evaluate the quality of white wine.

3.
Pharmaceuticals (Basel) ; 9(3)2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27529258

RESUMO

Benefits to health from a high consumption of fruits and vegetables are well established and have been attributed to bioactive secondary metabolites present in edible plants. However, the effects of specific health-related phytochemicals within a complex food matrix are difficult to assess. In an attempt to address this problem, we have used elicitation to improve the nutraceutical content of seedlings of Brassica oleracea grown under controlled conditions. Analysis, by LC-MS, of the glucosinolate, isothiocyanate and phenolic compound content of juices obtained from sprouts indicated that elicitation induces an enrichment of several phenolics, particularly of the anthocyanin fraction. To test the biological activity of basal and enriched juices we took advantage of a recently developed in vitro model of inflamed human intestinal epithelium. Both sprouts' juices protected intestinal barrier integrity in Caco-2 cells exposed to tumor necrosis factor α under marginal zinc deprivation, with the enriched juice showing higher protection. Multivariate regression analysis indicated that the extent of rescue from stress-induced epithelial dysfunction correlated with the composition in bioactive molecules of the juices and, in particular, with a group of phenolic compounds, including several anthocyanins, quercetin-3-Glc, cryptochlorogenic, neochlorogenic and cinnamic acids.

4.
Food Chem ; 201: 101-9, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868554

RESUMO

Epidemiological studies show an inverse association between Brassica consumption and chronic diseases. Phytochemicals are thought to be beneficial for human health and therefore responsible for this protective effect. Increasing their levels into Brassica food is considered an expedient nutritional strategy that can be achieved through the manipulation of growth conditions by elicitors. In this work we systematically evaluated the influence of treatment with different elicitors (sucrose, mannitol, NaCl, 1-aminocyclopropane-L-carboxylic acid, salicylic acid and methyl jasmonate) on the phytochemical composition of broccoli sprouts. The content of total and single glucosinolates, total phenolic compounds, total flavonoids, total anthocyanins, vitamin C and E and ß-carotene was assessed. The exposure to different elicitors produced concentration- and elicitor-dependent specific changes in the content of all the phytochemicals considered. Sucrose, identified as the most effective elicitor by principal component analysis, induced a significant increase of total and specific glucosinolates, vitamin C, total anthocyanins and polyphenols. Sucrose is likely to represent an effective tool to increase the nutritional value of broccoli sprouts.


Assuntos
Antocianinas/análise , Brassica/química , Glucosinolatos/análise , Fenóis/análise , Plântula/química , Humanos
5.
J Hypertens ; 33(7): 1465-79, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25807219

RESUMO

OBJECTIVES: Renal damage precedes occurrence of stroke in high-sodium/low-potassium-fed stroke-prone spontaneously hypertensive rat (SHRSP). We previously reported a marked suppression of uncoupling protein-2 (UCP2) upon high-salt Japanese-style diet in SHRSP kidneys. Vegetable compounds are known to exert protective effects in cardiovascular diseases. We aimed at evaluating the impact of Brassica oleracea sprouts juice toward renal damage in Japanese diet-fed SHRSP and exploring the role of 5'-adenosine monophosphate-activated protein kinase (AMPK)/NAD-dependent deacetylase sirtuin-1 (SIRT1)/peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α)/peroxisome proliferator-activated receptor-α (PPARα)/UCP2 axis. METHODS: SHRSP received Japanese diet for 4 weeks. A group of SHRSP received Japanese diet and B. oleracea. A third group received Japanese diet, B. oleracea, and PPARα inhibitor (GW6471). A group of SHRSP fed with regular diet served as control. RESULTS: Japanese diet induced marked increases of oxidative stress, inflammation, and proteinuria, along with glomerular and tubular damage, as compared with regular diet. A significant suppression of AMPK/UCP2 pathway was observed. Despite Japanese diet feeding, concomitant administration of B. oleracea prevented oxidative stress accumulation, inflammation, renal damage, and proteinuria. All components of the UCP2 regulatory pathway were significantly increased by B. oleracea. Superoxide dismutase 2 and phosphoendothelial nitric oxide synthase were also stimulated. Addition of PPARα inhibitor to B. oleracea and Japanese diet significantly reduced the B. oleracea beneficial effects. SBP levels were comparable among the different groups of rats.In vitro, UCP2 inhibition by genipin offset the antioxidant effect of B. oleracea in renal mesangial and proximal tubular cells. CONCLUSION: B. oleracea administration prevented renal damage in salt-loaded SHRSP, independently from SBP, with parallel stimulation of AMPK/SIRT1/PGC1α/PPARα/UCP2 axis. Stimulation of the latter mechanism may provide relevant renal protective effect and play a therapeutic role in target organ damage progression in hypertension.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Brassica/química , Canais Iônicos/metabolismo , Nefropatias/prevenção & controle , Proteínas Mitocondriais/metabolismo , PPAR alfa/metabolismo , Extratos Vegetais/administração & dosagem , Cloreto de Sódio na Dieta/efeitos adversos , Animais , Antioxidantes/farmacologia , Pressão Sanguínea/fisiologia , Dieta/efeitos adversos , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/metabolismo , Mesângio Glomerular/patologia , Hipertensão/complicações , Iridoides/farmacologia , Nefropatias/induzido quimicamente , Nefropatias/etiologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Estresse Oxidativo/efeitos dos fármacos , Proteinúria/induzido quimicamente , Proteinúria/prevenção & controle , Ratos , Ratos Endogâmicos SHR , Plântula/química , Acidente Vascular Cerebral/etiologia , Proteína Desacopladora 2
6.
Food Chem ; 179: 336-42, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25722174

RESUMO

Wine exerts beneficial effects on human health when it is drunk with moderation. Nevertheless, wine may also contain components negatively affecting human health. Among these, sulfites may induce adverse effects after ingestion. We examined total polyphenols and flavonoids content, phenolics profile and antioxidant activity of eight organic red wines produced without sulfur dioxide/sulfites addition in comparison to those of eight conventional red wines. Polyphenols and flavonoids content were slightly higher in organic wines in respect to conventional wines, however differences did not reach statistical significance. The phenolic acids profile was quite similar in both groups of wines. Antioxidant activity was higher in organic wines compared to conventional wines, although differences were not statistically significant. Our results indicate that organic red wines produced without sulfur dioxide/sulfites addition are comparable to conventional red wines with regard to the total polyphenols and flavonoids content, the phenolics profile and the antioxidant activity.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Polifenóis/química , Sulfitos/efeitos adversos , Vinho/análise , Humanos , Estresse Oxidativo , Sulfitos/química
7.
J Agric Food Chem ; 60(18): 4596-602, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22512471

RESUMO

Aminoethylcysteine ketimine decarboxylated dimer (AECK-DD) is a natural compound with antioxidant properties of a new family of sulfur-containing amino acids. It has been detected in human urine and plasma, in mammalian cerebellum, and in dietary vegetables. In this study, we first demonstrate the absorption of AECK-DD in mice from AECK-DD-supplemented diet, using both liquid chromatography with electrochemical detection and gas chromatography coupled with mass spectrometry. AECK-DD circulates in the plasma of supplemented mice at a micromolar concentration and is incorporated in liver tissue. The absorption of AECK-DD is dose dependent. The dehydrogenation product of AECK-DD was also identified in plasma and liver of mice fed the AECK-DD-supplemented diet. A significant increase in plasma antioxidant potential was measured in mice fed AECK-DD-supplemented diet with respect to mice fed the control diet. These results demonstrate for the first time the absorption of AECK-DD from diet and the physiological relevance of this compound through its antioxidant action in vivo.


Assuntos
Antioxidantes/metabolismo , Absorção Intestinal , Morfolinas/metabolismo , Animais , Antioxidantes/análise , Camundongos , Camundongos Endogâmicos BALB C , Morfolinas/sangue , Distribuição Aleatória , Verduras/química
8.
Int J Mol Sci ; 12(5): 3072-84, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21686170

RESUMO

Aminoethylcysteine ketimine decarboxylated dimer is a natural sulfur-containing compound detected in human plasma and urine, in mammalian brain and in many common edible vegetables. Over the past decade many studies have been undertaken to identify its metabolic role. Attention has been focused on its antioxidant properties and on its reactivity against oxygen and nitrogen reactive species. These properties have been studied in different model systems starting from plasma lipoproteins to specific cellular lines. All these studies report that aminoethylcysteine ketimine decarboxylated dimer is able to interact both with reactive oxygen and nitrogen species (hydrogen peroxide, superoxide anion, hydroxyl radical, peroxynitrite and its derivatives). Its antioxidant activity is similar to that of Vitamin E while higher than other hydrophilic antioxidants, such as trolox and N-acetylcysteine.


Assuntos
Depuradores de Radicais Livres/farmacologia , Morfolinas/farmacologia , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/metabolismo , Morfolinas/química , Morfolinas/metabolismo , Espécies Reativas de Nitrogênio/química , Espécies Reativas de Oxigênio/química , Enxofre/química
9.
J Agric Food Chem ; 58(19): 10677-83, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20822144

RESUMO

Despite the wide literature describing the biological effects of polyphenols, scarce data are available on their content in the human diet. This study examined total polyphenols content, free and total phenolic acids profile, and antioxidant activity of different commercial beers types (abbey, ale, bock, wheat, lager, pilsner, and dealcoholized). Ferulic acid is by far the most abundant phenolic acid in beers, followed by sinapic, vanillic, caffeic, p-coumaric, and 4-hydroxyphenylacetic acids. Ferulic, caffeic, syringic, sinapic, and, to a lesser extent, vanillic acids are present in beers mainly as bound forms, whereas p-coumaric and 4-hydroxyphenylacetic acids are generally present equally in free and bound forms. Total polyphenols and phenolic acids contents greatly vary among different beer types (i.e., total polyphenols, from 366 µg/mL gallic acid equivalents for dealcoholized beers to 875 µg/mL gallic acid equivalents for bock beers, with higher values measured in bock, abbey, and ale beers and lower values in dealcoholized beers). Similarly, the antioxidant activity measured with the ferric reducing antioxidant power (FRAP) assay is remarkably different depending on beer type (from 1525 µM for dealcoholized beers to 4663 µM for bock beers), with higher values in bock, abbey, and ale beers and lower values in dealcoholized beers. FRAP values strictly correlate with polyphenols and phenolic acids content. The contribution of single phenolic acids to the antioxidant activity measured with FRAP assay was also studied.


Assuntos
Antioxidantes/farmacologia , Cerveja/análise , Flavonoides/análise , Fenóis/análise , Ácidos Cumáricos/análise , Etanol/análise , Compostos Férricos/química , Flavonoides/farmacologia , Oxirredução , Fenóis/farmacologia , Polifenóis
10.
J Agric Food Chem ; 57(7): 2711-8, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-19334754

RESUMO

Despite the vast literature describing the biological effects of phenolic compounds, rather scarce data are available on their absorption from diet in humans. The present study focused on the absorption in humans of phenolic acids from white wine, particularly hydroxycinnamic acids and their esters with tartaric acid. The results obtained indicate that, following a single wine drink, hydroxycinnamic acids from white wine are absorbed from the gastrointestinal tract and circulate in the blood after being largely metabolized to the form of glucuronide and sulfate conjugates. Unmodified tartaric acid esters of hydroxycinnamic acids from wine are present in human plasma at low levels, if any. Wine hydroxycinnamic acids, although present in wine as conjugated forms, are still bioavailable to humans.


Assuntos
Ácidos Cumáricos/farmacocinética , Flavonoides/farmacocinética , Fenóis/farmacocinética , Vinho/análise , Absorção , Adulto , Ácidos Cumáricos/análise , Ácidos Cumáricos/sangue , Feminino , Flavonoides/análise , Trato Gastrointestinal/metabolismo , Humanos , Absorção Intestinal , Masculino , Pessoa de Meia-Idade , Fenóis/análise , Polifenóis , Tartaratos/química
11.
Am J Clin Nutr ; 86(3): 604-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17823423

RESUMO

BACKGROUND: Epidemiologic and intervention studies indicate that both diet as a whole and single dietary components are involved in the risk of atherosclerosis. The resistance of LDL to oxidative modification is an ex vivo indicator of risk, which is modulated by dietary components. Coffee contains phenolic compounds with antioxidant activity. These molecules are found in plasma after the consumption of coffee, and it has been shown that, in vitro, they are able to decrease the susceptibility of LDL to oxidation. OBJECTIVE: The aim of this study was to evaluate the effect of coffee consumption on the redox status of LDL as modulated by the possible incorporation of phenolic acids into LDL. DESIGN: Ten healthy volunteers, after an overnight fast, drank 200 mL filtered coffee. Blood was drawn before and 30 and 60 min after drinking. Changes in LDL redox status were evaluated by the measure of LDL resistance to oxidative modification and the concentration of LDL(-), a mildly modified, electronegative LDL subfraction. Chlorogenic and phenolic acids concentration in LDL were measured by electrochemical HPLC. RESULTS: The resistance of LDL to oxidative modification increased significantly after coffee drinking, but the LDL(-) concentration did not increase. The concentration into LDL of conjugated forms of caffeic, p-coumaric, and ferulic acids increased significantly after coffee drinking. CONCLUSION: Drinking 200 mL (1 cup) coffee induces an increase in the resistance of LDL to oxidative modification, probably as a result of the incorporation of coffee's phenolic acids into LDL.


Assuntos
Antioxidantes/farmacologia , Café/química , Hidroxibenzoatos/farmacologia , Lipoproteínas LDL/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Adulto , Antioxidantes/análise , Antioxidantes/metabolismo , Bebidas , Ácidos Cafeicos/análise , Ácidos Cafeicos/farmacologia , Ácido Clorogênico/análise , Ácido Clorogênico/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/análise , Ácidos Cumáricos/farmacologia , Jejum , Feminino , Humanos , Hidrólise , Hidroxibenzoatos/análise , Hidroxibenzoatos/metabolismo , Cinética , Lipoproteínas LDL/química , Masculino , Oxirredução , Propionatos
12.
Free Radic Res ; 41(7): 748-56, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17577735

RESUMO

In view of the promising use of n-3 polyunsaturated fatty acids (PUFAs) in the prevention and treatment of neurological diseases, it is necessary to ascertain the lack of detrimental oxidative effects. We evaluated short- and long-term effects of 25, 50 and 75 muM docosahexaenoic acid (DHA) supplementation on the oxidative status of C6 glial cells. DHA was incorporated into cells dose and time dependently without any cytotoxic effect. Reactive oxygen species (ROS) level was related to DHA dose and supplementation time. At the lowest dose no significant increase in ROS values was observed at hour 24. Low doses of DHA strengthened the cellular antioxidant defence system as highlighted by a raise in both GPX and catalase activity, and the decreased levels of lipid peroxidation. This effect was pronounced at 24 h of supplementation, almost disappeared at hour 48, while after 72 h an opposite effect was observed: lipid peroxidation increased concomitantly with DHA doses. Therefore, the final effect of DHA on cellular redox status is dependent on dose and time supplementation.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos/metabolismo , Citometria de Fluxo , Glioblastoma , Glutationa/metabolismo , Cinética , Lipídeos/isolamento & purificação , Ratos , Superóxidos/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análise
13.
J Nat Prod ; 70(6): 1046-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17469872

RESUMO

While investigating the antioxidant properties of aminoethylcysteine ketimine decarboxylated dimer (1) (a natural substance occurring in biological fluids such as human urine and plasma and in bovine cerebellum), a previously unreported oxidation product was obtained. This compound was identified and characterized through comparison with an authentic sample prepared via Pd-catalyzed dehydrogenation of 1. This molecule is an example of an alternative oxidation pathway involving 1.


Assuntos
Antioxidantes/síntese química , Morfolinas/síntese química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Bovinos , Cerebelo/química , Humanos , Estrutura Molecular , Morfolinas/sangue , Morfolinas/química , Morfolinas/urina , Oxirredução , Paládio/química
14.
Platelets ; 18(3): 224-43, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17497435

RESUMO

Epidemiological studies suggest that high polyphenols intake from diet is associated with reduced risk for cardiovascular diseases. Platelet aggregation is a crucial mechanism in the pathogenesis and clinical expression of coronary acute syndrome, and there is extensive evidence that antiplatelet therapy reduces cardiovascular disease risk. In this review, the available literature on the effect of polyphenols supplementation on platelet aggregation in humans or animal models has been critically analyzed, taking into consideration the different experimental protocols employed. In some studies, polyphenols supplementation did not show any effect on platelet aggregation. However, in the most of the studies, polyphenols supplementation, either as purified compounds or food extracts, showed some inhibitory effects, both in humans and in animal models. The extent of the inhibition varies in a wide range, depending on the experimental conditions used. The observed inhibitory effect of polyphenols on platelet aggregation might explain, at least in part, the epidemiological data on beneficial effect of dietary polyphenols on cardiovascular disease risk and suggests a role for polyphenols in helping to prevent cardiovascular diseases.


Assuntos
Dieta , Flavonoides/administração & dosagem , Fenóis/administração & dosagem , Agregação Plaquetária , Suplementos Nutricionais , Humanos , Polifenóis
15.
J Nutr Biochem ; 17(1): 14-22, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16242314

RESUMO

In spite of the wide literature describing the biological effects of phenolic compounds, scarce data are available on their absorption from diet. In the present work, we studied the absorption in humans of phenolic acids from beer, a common beverage rich in different phenolic acids with related chemical structures. Beer was analyzed for free and total (free+bound) phenolic acids. Ferulic, caffeic and sinapic acids were present in beer mainly as bound forms, while 4-hydroxyphenylacetic acid and p-coumaric acid were present mainly as free forms. Vanillic acid was present equally in the free and bound forms. Plasma samples were collected before and 30 and 60 min after beer administration and analyzed for free and conjugated phenolic acid content. A significant two- to fourfold increase in plasma levels of phenolic acids was detected with peak concentrations at 30 min after beer ingestion. 4-Hydroxyphenylacetic acid was present in plasma mainly as nonconjugated forms while p-coumaric acid was present equally as nonconjugated and conjugated forms. Ferulic, vanillic and caffeic acids were present in plasma predominantly as conjugated forms, with a slight prevalence of sulfates with respect to glucuronates. Our results indicate that phenolic acids from beer are absorbed from the gastrointestinal tract and are present in blood after being largely metabolized to the form of glucuronide and sulfate conjugates. The extent of conjugation is related to the chemical structure of phenolic acids: the monohydroxy derivatives showing the lowest conjugation degree and the dihydroxy derivatives showing the highest one.


Assuntos
Cerveja/análise , Hidroxibenzoatos/farmacocinética , Absorção , Adulto , Ácidos Cafeicos/farmacocinética , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/farmacocinética , Feminino , Humanos , Hidroxibenzoatos/sangue , Masculino
16.
Free Radic Res ; 39(8): 865-74, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16036367

RESUMO

n-3 polyunsaturated fatty acids (PUFAs) have been described to have beneficial effects on brain development and in the prevention and treatment of brain damage. C6 glioma cells were incubated with 100 microM of either C20:4n-6 (ARA), or C20:5n-3 (EPA), or C22:6n-3 (DHA) for different time periods to assess whether these acids altered the cellular oxidative state. The ARA and EPA were promptly metabolised to C22:4n-6 and C22:5n-3, respectively, whereas DHA treatment simply increased the amount of DHA in the cells. Cell viability was not affected by ARA, while a cytotoxic effect was observed 72 h after n-3 PUFAs supplementation. The levels of reactive oxygen species and thiobarbituric acid-reactive substances were significantly higher in DHA-treated cells than in EPA- and ARA-treated groups. This modification in the oxidative cellular status was also highlighted by a significant increase in catalase activity and a decrease in glutathione content in DHA-supplemented cells. Glucose-6-phosphate dehydrogenase activity, an enzyme involved in redox regulation, and O2*- release were significantly increased both in EPA and DHA groups. The effect of DHA was more severe than that of EPA. No significant changes were observed in the ARA group with respect to untreated cells. These data show that EPA and DHA induce alterations in the oxidative status that could affect the glial function.


Assuntos
Ácido Araquidônico/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Neuroglia/efeitos dos fármacos , Animais , Ácido Araquidônico/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/toxicidade , Ácido Eicosapentaenoico , Ácidos Graxos Insaturados/toxicidade , Citometria de Fluxo , Glioblastoma , Glucosefosfato Desidrogenase/biossíntese , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Neuroglia/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Superóxido Dismutase , Tiobarbitúricos/metabolismo
17.
Antioxid Redox Signal ; 7(1-2): 25-31, 2005 Jan-Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15650393

RESUMO

Lipid oxidation and environmental pollutants are major sources of alpha,beta-unsaturated aldehydes such as acrolein and 4-hydroxynonenal. Acrolein (2-propenal), a major product of organic combustion such as tobacco smoke, represents the most reactive alpha,beta-unsaturated aldehyde, with high reactivity toward nucleophilic targets such as sulfhydryl groups. To investigate how acrolein affects respiratory tract cell activation, we exposed either primary (NHBE) or immortalized human bronchial epithelial cells (HBE1) to 0-25 microM acrolein, and determined effects on basal and tumor necrosis factor-alpha (TNFalpha)-induced production of the chemokine interleukin (IL)-8. Cell exposure to acrolein dose-dependently suppressed IL-8 mRNA levels in HBE1 cells (26, 40, and 79% at 5, 10, and 25 microM acrolein concentrations, respectively) and resulted in corresponding decreases in IL-8 production. Studies of nuclear factor-kappaB (NFkappaB) activation, an essential event in IL-8 production, showed decreased TNFalpha-induced NFkappaB activation by acrolein, illustrated by inhibition of nuclear translocation of NFkappaB and reduced IkappaBalpha degradation. Immunochemical analysis of IkappaB kinase (IKK), a redox-sensitive regulator of NFkappaB activation, indicated direct modification of the IKK beta-subunit by acrolein, suggesting that acrolein may act directly on IKK. In summary, our results demonstrate that acrolein can suppress inflammatory processes in the airways by inhibiting epithelial IL-8 production through direct or indirect inhibitory effects on NFkappaB activation.


Assuntos
Acroleína/farmacologia , Brônquios/citologia , Células Epiteliais/citologia , Interleucina-8/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Transporte Ativo do Núcleo Celular , Western Blotting , Brônquios/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/efeitos dos fármacos , Humanos , Quinase I-kappa B , Imuno-Histoquímica , Imunoprecipitação , Inflamação , Interleucina-8/metabolismo , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Sistema Respiratório/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismo
18.
Free Radic Res ; 38(7): 705-14, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15453636

RESUMO

Aminoethylcysteine ketimine decarboxylated dimer (AECK-DD) is a natural sulphur compound present in human plasma and urine and in mammalian brain. Recently, it has been detected in many common dietary vegetables. The aim of the present study was to evaluate the ability of AECK-DD to affect cellular response of U937 human monocytic cells to tert-butyl hydroperoxide-induced oxidative stress. AECK-DD was incorporated into cells, as confirmed by GC-MS analyses, without any cytotoxic effect. A 24 h treatment with 50 and 250 microM AECK-DD resulted in the incorporation of 0.10 +/- 0.01 and 0.47 +/- 0.08ng AECK-DD x 10(6) cells, respectively. U937 cells pretreated with AECK-DD (in the range 4-100 microM) showed an increased resistance to tert-butyl hydroperoxide-induced necrotic death, as revealed by a higher percent of survival measured at all incubation times with respect to control cells. Moreover, the protective effect exhibited by AECK-DD is significantly stronger with respect to that obtained with other common antioxidants (N-acetyl cysteine and trolox) and comparable, although somewhat higher, to that of vitamin E. This effect seems to be due to the ability of AECK-DD to reduce glutathione depletion and to inhibit lipid peroxidation during tert-butyl hydroperoxide treatment. It can be concluded that AECK-DD protects cultured human monocytic cells against tert-butyl hydroperoxide-induced oxidative stress and subsequent cell death, likely through an antioxidant action inside the cell. Due to its presence in both human plasma and urine, AECK-DD may play a role in the modulation of oxidative processes in vivo.


Assuntos
Morfolinas/sangue , Morfolinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , terc-Butil Hidroperóxido/farmacologia , Antioxidantes/farmacologia , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Humanos , Morfolinas/química , Oxidantes/metabolismo , Compostos de Enxofre/química , Compostos de Enxofre/metabolismo , Compostos de Enxofre/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Células U937
20.
J Agric Food Chem ; 50(21): 6211-6, 2002 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-12358504

RESUMO

Coffee and tea are widely consumed beverages, but only tea has been studied for its antioxidant capacity (AC) in vivo. The aim of this study was to compare the capacities of coffee and tea to affect plasma redox homeostasis in humans. The AC of plasma before and after supplementation with 200 mL of beverages (0, 1, and 2 h) was measured by the TRAP and crocin tests. The crocin test detected an increase in plasma AC only in subjects supplemented with coffee (+7% at peak time), whereas the TRAP method showed an increase in plasma AC after consumption of both coffee and tea (+6 and +4%, respectively, at peak time). Both beverages induced a significant increase in plasma uric acid (+5 and +7%, respectively). Uric acid strongly affects the results obtained by the TRAP test and does not affect those obtained by the crocin test. We can thus argue that uric acid is the main component responsible for the plasma AC increase after tea drinking, whereas molecules other than uric acid (probably phenolic compounds) are likely to be responsible for the increase in plasma AC after coffee drinking.


Assuntos
Antioxidantes/análise , Café , Flavonoides , Carotenoides/sangue , Carotenoides/química , Depuradores de Radicais Livres , Humanos , Lipídeos/sangue , Oxirredução , Peróxidos/sangue , Fenóis/análise , Fenóis/sangue , Polímeros/análise , Polifenóis , Chá , Ácido Úrico/sangue
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