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1.
Br J Nutr ; 105(12): 1718-23, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21294933

RESUMO

Moderate wine consumption has been shown to lower cardiovascular risk. One of the mechanisms could involve the control of postprandial hyperlipaemia, a well-defined risk factor for atherosclerosis, reasonably by reducing the absorption of lipid oxidised species from the meal. The objective of the present study was to investigate whether wine consumption with the meal is able to reduce the postprandial increase in plasma lipid hydroperoxides and cholesterol oxidation products, in human subjects. In two different study sessions, twelve healthy volunteers consumed the same test meal rich in oxidised and oxidisable lipids (a double cheeseburger), with 300 ml of water (control) or with 300 ml of red wine (wine). The postprandial plasma concentration of cholesterol oxidation products was measured by GC-MS. The control meal induced a significant increase in the plasma concentration of lipid hydroperoxides and of two cholesterol oxidation products, 7-ß-hydroxycholesterol and 7-ketocholesterol. The postprandial increase in lipid hydroperoxides and cholesterol oxidation products was fully prevented by wine when consumed with the meal. In conclusion, the present study provides evidence that consumption of wine with the meal could prevent the postprandial increase in plasma cholesterol oxidation products.


Assuntos
Colesterol/sangue , Peróxidos Lipídicos/sangue , Estresse Oxidativo/fisiologia , Polifenóis/análise , Período Pós-Prandial/fisiologia , Vinho , Adulto , Análise de Variância , Colesterol/metabolismo , Estudos Cross-Over , Feminino , Humanos , Masculino , Projetos Piloto
2.
Br J Nutr ; 100(6): 1276-82, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18439332

RESUMO

Epidemiological studies indicate a J-shaped relationship linking coffee consumption and cardiovascular risk, suggesting that moderate coffee consumption can be beneficial. Platelet aggregation is of critical importance in thrombotic events, and platelets play a major role in the aetiology of several CVD. The aim of this study was to evaluate the effect of coffee drinking on platelet aggregation ex vivo, using caffeine as control. A crossover study was performed on ten healthy subjects. In two different sessions, subjects drank 200 ml coffee, containing 180 mg caffeine, or a capsule of caffeine (180 mg) with 200 ml water. Platelets were separated from plasma at baseline and 30 and 60 min after coffee drinking. Platelet aggregation was induced with three different agonists: collagen, arachidonic acid and ADP. Coffee drinking inhibited collagen (P < 0.05 from baseline at time 30 min) and arachidonic acid (P < 0.05 from baseline at time 60 min) induced platelet aggregation. Caffeine intake did not affect platelet aggregation induced by the three agonists. Coffee consumption induced a significant increase of platelet phenolic acids (likely present as glucuronate and sulphate derivatives), caffeic acid, the principal phenolic acid in coffee, raising from 0.3 (SEM 0.1) to 2.4 (SEM 0.6) ng/mg (P < 0.01). Caffeine was not detectable in platelets. Coffee drinking decreases platelet aggregation, and induces a significant increase in phenolic acid platelet concentration. The antiplatelet effect of coffee is independent from caffeine and could be a result of the interaction of coffee phenolic acids with the intracellular signalling network leading to platelet aggregation.


Assuntos
Plaquetas/efeitos dos fármacos , Cafeína/farmacologia , Café , Hidroxibenzoatos/sangue , Adulto , Plaquetas/metabolismo , Cafeína/sangue , Células Cultivadas , Estudos Cross-Over , Ingestão de Líquidos/fisiologia , Feminino , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Adulto Jovem
3.
J Agric Food Chem ; 50(20): 5735-41, 2002 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-12236707

RESUMO

Despite extensive literature describing the biological effects of polyphenols, little is known about their absorption from diet, one major unresolved point consisting of the absorption of the bound forms of polyphenols. In this view, in the present work we studied the absorption in humans of phenolic acids from coffee, a common beverage particularly rich in bound phenolic acids, such as caffeic acid, ferulic acid, and p-coumaric acid. Coffee brew was analyzed for free and total (free + bound) phenolic acids. Chlorogenic acid (5'-caffeoylquinic acid), a bound form of caffeic acid, was present in coffee at high levels, while free phenolic acids were undetectable. After alkaline hydrolysis, which released bound phenolic acids, ferulic acid, p-coumaric acid, and high levels of caffeic acid were detected. Plasma samples were collected before and 1 and 2 h after coffee administration and analyzed for free and total phenolic acid content. Two different procedures were applied to release bound phenolic acids in plasma: beta-glucuronidase treatment and alkaline hydrolysis. Coffee administration resulted in increased total plasma caffeic acid concentration, with an absorption peak at 1 h. Caffeic acid was the only phenolic acid found in plasma samples after coffee administration, while chlorogenic acid was undetectable. Most of caffeic acid was present in plasma in bound form, mainly in the glucuronate/sulfate forms. Due to the absence of free caffeic acid in coffee, plasma caffeic acid is likely to be derived from hydrolysis of chlorogenic acid in the gastrointestinal tract.


Assuntos
Café/química , Hidroxibenzoatos/farmacocinética , Absorção , Disponibilidade Biológica , Proteínas Sanguíneas/metabolismo , Ácidos Cafeicos/análise , Ácidos Cafeicos/sangue , Ácidos Cafeicos/metabolismo , Ácido Clorogênico/análise , Ácido Clorogênico/metabolismo , Ácidos Cumáricos/análise , Glucuronidase/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Hidroxibenzoatos/análise , Cinética , Propionatos
4.
Free Radic Biol Med ; 30(9): 1036-44, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11316584

RESUMO

The aim of the present study was to verify the extent of oxidative stress induced by a meal at plasma and LDL level, and to investigate the capacity of red wine to counteract this action. In two different sessions, six healthy men ate the same test meal consisting of "Milanese" meat and fried potatoes. The meal was taken either with 400 ml red wine or with an isocaloric hydroalcoholic solution. Oxidative stress at plasma level was estimated through the measure of ascorbic acid, alpha-tocopherol, protein SH groups, uric acid, and antioxidant capacity, measured before and 1 and 3 h after the meal. The change in the resistance of LDL to oxidative modification was taken as an index of exposure to pro-oxidants. The susceptibility to Cu(II)-catalyzed oxidation of baseline and postprandial LDL was measured as conjugated dienes formation, tryptophan residues, and relative electrophoretic mobility. The experimental meal taken with wine provoked a significant increase in the total plasma antioxidant capacity and in the plasma concentration of alpha-tocopherol and SH groups. Postprandial LDL was more susceptible to metal-catalyzed oxidation than the homologous baseline LDL after the ethanol meal. On the contrary, postprandial LDL obtained after the wine meal was as resistant or more resistant to lipid peroxidation than fasting LDL.


Assuntos
Lipoproteínas LDL/sangue , Vinho , Adulto , Doença das Coronárias/sangue , Doença das Coronárias/etiologia , Gorduras na Dieta/administração & dosagem , Ingestão de Alimentos/fisiologia , Radicais Livres/sangue , Humanos , Técnicas In Vitro , Cinética , Peróxidos Lipídicos/sangue , Lipoproteínas LDL/química , Masculino , Oxirredução , Estresse Oxidativo , Vitamina E/sangue
5.
Free Radic Biol Med ; 30(7): 722-33, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11275472

RESUMO

Ceramide acts as second messenger in the signal transduction triggered by a variety of stress stimuli and extracellular agents. Stress response through ceramide is involved in the development of many human diseases, such as atherosclerosis, inflammation, neurodegenerative disorders, and acquired immunodeficiency syndrome. Dietary polyphenols have been reported to exert a beneficial effect on the onset and development of most of these human chronic-degenerative pathologies. However, the mechanisms underlying this beneficial effect are mostly not understood at the present. To investigate the ability of polyphenols in modulating fundamental cellular functions, we studied the effect of caffeic acid, a widespread phenolic acid largely present in human diet, in the modulation of ceramide-induced signal transduction pathway leading to apoptosis in U937 cells, in comparison with other established antioxidants of nutritional interest (N-acetylcysteine, d-alpha-tocopherol acetate and ascorbic acid). Our results indicate that caffeic acid efficiently inhibits both ceramide-induced NF-kappaB binding activity and apoptosis at micromolar concentration. Other antioxidants tested are totally ineffective in inhibiting apoptosis, although affecting NF-kappaB activation. Caffeic acid was found to inhibit protein tyrosine kinase activity, suggesting that this mechanism can be on the basis of the inhibition of apoptosis. Our results suggest that dietary caffeic acid might modulate ceramide-induced signal transduction pathway and NF-kappaB activation through either antioxidant and nonantioxidant mechanisms.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Ceramidas/farmacologia , Monócitos/efeitos dos fármacos , NF-kappa B/metabolismo , Fragmentação do DNA , Inibidores Enzimáticos/farmacologia , Dissulfeto de Glutationa/metabolismo , Humanos , Cinética , Monócitos/citologia , Monócitos/metabolismo , Peróxidos/metabolismo , Inibidores de Proteínas Quinases , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Células U937
6.
Free Radic Biol Med ; 29(11): 1106-14, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11121717

RESUMO

The measure of antioxidant capacity (AC) considers the cumulative action of all the antioxidants present in plasma and body fluids, thus providing an integrated parameter rather than the simple sum of measurable antioxidants. The capacity of known and unknown antioxidants and their synergistic interaction is therefore assessed, thus giving an insight into the delicate balance in vivo between oxidants and antioxidants. Measuring plasma AC may help in the evaluation of physiological, environmental, and nutritional factors of the redox status in humans. Determining plasma AC may help to identify conditions affecting oxidative status in vivo (e.g., exposure to reactive oxygen species and antioxidant supplementation). Moreover, changes in the plasma AC after supplementation with galenic antioxidants or with antioxidant-rich foods may provide information on the absorption and bioavailability of nutritional compounds. Consequently, this review discusses the rationale, interpretation, confounding factors, measurement limits, and human applications of the measure of plasma AC.


Assuntos
Antioxidantes/análise , Oxirredução , Líquidos Corporais/química , Meio Ambiente , Radicais Livres , Humanos , Cinética , Fenômenos Fisiológicos da Nutrição , Estresse Oxidativo , Fenóis , Fumar
7.
Biochim Biophys Acta ; 1474(2): 219-25, 2000 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-10742602

RESUMO

Caffeic acid (CA) is a common constituent of human diet while pine bark extract (PBE) is utilized either as nutritional supplement or as phytochemical remedy for different diseases. CA and PBE, are reported as efficient antioxidants and more recently have been described to modulate cellular response to oxidative challenge and to possess many other biological activities, i.e. anti-inflammatory, antimutagenic, antitumoral effects. In order to investigate in depth the mechanism of action of these polyphenols, the effects of CA and PBE on the activity of some protein kinases involved in the regulation of fundamental cellular processes were studied in vitro: phosphorylase kinase (PhK), protein kinase A (PKA), protein kinase C (PKC). PBE at the concentration of 20 microg/ml (corresponding to 69 microM catechin equivalents) inhibited PKA, PhK and PKC by about 90, 59, 57%, respectively, while 100 microM CA inhibited by 37, 52 and 54%, respectively. Considerable inhibitions have been still observed at even lower concentrations of CA and PBE. For PhK and PKA, the inhibition follows a non-competitive mechanism. CA also inhibits PKC activity in a partially purified cellular extract. The results suggest a possible involvement of CA and PBE in modulation of cellular functions.


Assuntos
Ácidos Cafeicos/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fosforilase Quinase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Fosforilase Quinase/metabolismo , Proteína Quinase C/metabolismo , Árvores/química
8.
J Nutr Biochem ; 11(2): 76-80, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10715591

RESUMO

The positive association of a moderate intake of alcoholic beverages with a low risk for cardiovascular disease, in addition to ethanol itself, may be linked to their polyphenol content. This article describes the effect of acute ingestion of beer, dealcoholized beer, and ethanol (4.5% v/v) on the total plasma antioxidant status of subjects, and the change in the high performance liquid chromatography profile of some selected phenolic acids (caffeic, sinapic, syringic, and vanillic acids) in 14 healthy humans. Plasma was collected at various times: before (T0), 1 hour after (T1), and 2 hours after (T2) drinking. The study is part of a larger research planned to identify both the impact of brewing on minor components potentially present in beer and their metabolic fate in humans. Beer was able to induce a significant (P < 0.05) increase in plasma antioxidant capacity at T1 (mean +/- SD: T0 1,353 +/- 320 microM; T1 1,578 +/- 282 microM), returning close to basal values at T2. All phenolic acids measured in plasma tended to increase after beer intake (20% at T1, 40% at T2). Syringic and sinapic acid reached statistical significance (P < 0.05 by one-way analysis of variance-Fisher's test) at T1 and T2, respectively. Plasma metabolic parameters (glucose, total cholesterol, triglycerides, and uric acid) and plasma antioxidants (alpha-tocopherol and glutathione) remained unchanged. Ethanol removal impaired the absorption of phenolic acids, which did not change over the time of the experiment, accounting for the low (and not statistically significant) increase in plasma antioxidant capacity after dealcoholized beer drinking. Ethanol alone did not affect plasma antioxidant capacity or any of the antioxidant and metabolic parameters measured.

9.
J Agric Food Chem ; 47(4): 1453-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10563998

RESUMO

The antioxidant activity of four derivatives of benzoic acid was systematically compared with the activity of the four homologous derivatives of cinnamic acid. The couples of compounds differed for the kind of aromatic substitution (p-hydroxy, p-hydroxymethoxy, p-hydroxydimethoxy, dihydroxy). The antioxidant activity was measured using (i) a competition kinetic test, to measure the relative capacity to quench peroxyl radical and (ii) the in vitro oxidative modification of human low-density lipoprotein (LDL), initiated by 2,2'-azobis(amidinopropane) dihydrochloride or catalyzed by Cu(II). In both models, cinnamic acids were more efficient than their benzoic counterparts. As for the influence of the aromatic substitution, in the kinetic test the antioxidant activity increased in the sequence p-hydroxy < p-hydroxymethoxy < dihydroxy < p-hydroxydimethoxy. In contrast, in the LDL system, the dihydroxy acids had an antioxidant capacity equal to or higher than that of the p-hydroxydimethoxy acids.


Assuntos
Antioxidantes , Benzoatos/farmacologia , Cinamatos/farmacologia , Lipoproteínas LDL/efeitos dos fármacos , Benzoatos/química , Cinamatos/química , Humanos , Cinética , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Relação Estrutura-Atividade
10.
Free Radic Biol Med ; 25(9): 1098-105, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9870564

RESUMO

Nonvitamin phenolic compounds are ubiquitous in food plants and therefore potentially present in human plasma in a diet-dependent concentration. The aim of this study was to evaluate the ability of caffeic acid, a phenolic acid with antioxidant activity, to affect cellular response in U937 human monocytic cells to t-butyl hydroperoxide-induced oxidative stress. In our experimental conditions caffeic acid was incorporated into cells without any cytotoxic effect. Caffeic acid-treated cells showed an increased resistance to oxidative challenge, as revealed by an higher percent of survival and the maintenance of an higher proliferative capacity in respect to control cells. This effect seems to be due to the ability of caffeic acid to reduce glutathione depletion and to inhibit lipid peroxidation during tBOOH treatment. It can be concluded that caffeic acid exerts an antioxidant action inside the cell, responsible for the observed modulation of the cellular response to oxidative challenge. Due to its presence in the diet, therefore, caffeic acid may play a role in the modulation of oxidative processes in vivo.


Assuntos
Ácidos Cafeicos/farmacologia , Monócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , terc-Butil Hidroperóxido/farmacologia , Antioxidantes/farmacologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dieta , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Células U937 , Vitamina E/metabolismo
11.
Dig Dis Sci ; 43(6): 1332-8, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9635627

RESUMO

The relationship between chronic moderate beer consumption and oxidative stress was studied in rats. Animals were fed three different isocaloric diets for six weeks: a beer-containing diet (30% w/w), an ethanol-supplemented diet (1.1 g/100 g, the same as in the beer diet) and an alcohol-free basal diet. At the end of the feeding period, rats were analyzed for plasma and liver oxidative status. Some livers were isolated and exposed to ischemia-reperfusion to assess the additional oxidative stress determined by reperfusion. No significant differences in plasma antioxidant status were found among the three dietary groups. Lipoproteins from the beer group, however, showed a greater propensity to resist lipid peroxidation. Ischemia caused a decrease in liver energy and antioxidant status in all groups. Nevertheless, ATP was lower in the livers of rats exposed to the ethanol diet. During reperfusion, lipoperoxidation increased significantly in all groups. However, livers obtained from ethanol-treated rats showed the higher formation of lipoperoxides. In conclusion, a moderate consumption of beer in a well-balanced diet did not appear to cause oxidative stress in rats; moreover, probably through its minor components, beer could attenuate the oxidative action of ethanol by itself.


Assuntos
Cerveja , Etanol/farmacologia , Fígado/fisiopatologia , Estresse Oxidativo/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Dieta , Glutationa/metabolismo , Peroxidação de Lipídeos , Fígado/química , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/fisiopatologia , Substâncias Reativas com Ácido Tiobarbitúrico
12.
Free Radic Res ; 29(5): 427-34, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9925035

RESUMO

Heme-peroxidases, such as horseradish peroxidase (HRP), are among the most popular catalysts of low density lipoprotein (LDL) peroxidation. In this model system, a suitable oxidant such as H2O2 is required to generate the hypervalent iron species able to initiate the peroxidative chain. However, we observed that traces of hydroperoxides present in a fresh solution of linoleic acid can promote lipid peroxidation and apo B oxidation, substituting H2O2. Spectral analysis of HRP showed that an hypervalent iron is generated in the presence of H2O2 and peroxidizing linoleic acid. Accordingly, careful reduction of the traces of linoleic acid lipid hydroperoxide prevented formation of the ferryl species in HRP and lipid peroxidation. However, when LDL was oxidized in the presence of HRP, the ferryl form of HRP was not detectable, suggesting a Fenton-like reaction as an alternative mechanism. This was supported by the observation that carbon monoxide, a ligand for the ferrous HRP, completely inhibited peroxidation of LDL. These results are in agreement with previous studies showing that myoglobin ferryl species is not produced in the presence of phospholipid hydroperoxides, and emphasize the relevance of a Fenton-like chemistry in peroxidation of LDL and indirectly, the role of pre-existing lipid hydroperoxides.


Assuntos
Peroxidase do Rábano Silvestre/metabolismo , Peróxido de Hidrogênio/farmacologia , Lipoproteínas LDL/metabolismo , Apolipoproteínas B/metabolismo , Contaminação de Medicamentos , Humanos , Ferro/metabolismo , Cinética , Ácido Linoleico/farmacologia , Peroxidação de Lipídeos , Espectrofotometria
13.
J Agric Food Chem ; 46(2): 361-367, 1998 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-10554247

RESUMO

Using liquid/liquid extraction, three fractions were obtained from an Italian red wine containing single polyphenolic subfractions: (1) phenolic acids and quercetin-3-glucuronide, (2) catechins and quercetin-3-glucoside, and (3) anthocyanins. Beside the scavenging capacity of the different fractions against hydroxyl and peroxyl radicals, the in vitro inhibition of low density lipoprotein oxidation and platelet aggregation (two main events in the pathogenesis of atherosclerosis) were tested. The antioxidant activity of the fractions has been compared with that of the original red wine before and after dealcoholization. The anthocyanin fraction was the most effective both in scavenging reactive oxygen species and in inhibiting lipoprotein oxidation and platelet aggregation. This higher activity can be explained by both its high concentration in red wine and its antioxidant efficiency, which, at least for peroxyl radical scavenging, was three times as high as that of the other two fractions. Our results suggest that anthocyanins could be the key component in red wine in light of the protection against cardiovascular diseases, although this hypothesis needs in vivo evidence.

14.
Arch Biochem Biophys ; 342(1): 157-60, 1997 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9185624

RESUMO

Dietary supplementation of caffeic acid (0.2 and 0.8% w/w) in rats resulted in a statistically significant increase of alpha-tocopherol both in plasma and lipoprotein. While caffeic acid was not detectable in plasma under fasting conditions, in postprandial plasma it was present at micromole concentrations, doubling plasma total antioxidant capacity. Lipoproteins from caffeic acid-fed rats were more resistant than control to Cu2+-catalyzed oxidation, despite the lack of incorporation of caffeic acid in the particles. No significant effects on plasma and liver copper concentration, nor the increase in liver of Mn-superoxide dismutase reported in copper deficiency, were detected. These results demonstrate the physiological relevance of caffeic acid and its antioxidant action in vivo, through both a direct contribution to the antioxidant defense system and a sparing effect on alpha-tocopherol.


Assuntos
Antioxidantes/administração & dosagem , Ácidos Cafeicos/administração & dosagem , Lipoproteínas/sangue , Vitamina E/sangue , Animais , Cobre/metabolismo , Dieta , Fígado/metabolismo , Masculino , Período Pós-Prandial , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Ácido Úrico/sangue
15.
Int J Epidemiol ; 25(3): 513-20, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8671551

RESUMO

BACKGROUND: Increases in blood lipids have been observed in humans when coffee is brewed by the boiling method. The purpose of this study was to evaluate if giving up Italian coffee might reduce blood cholesterol levels. METHODS: Eighty-four normolipidaemic young adult males, after a 3-week baseline (BL), were randomly assigned to three different regimens of coffee consumption: espresso (E), mocha (M), and no coffee, but tea (T). The average coffee consumption during intervention (I) was 3.1 +/- 1.2 and 2.8 +/- 1.1 cups per day for espresso and mocha group respectively (espresso: 25-35 ml/cup; mocha: 40-50 ml/cup). Total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides were measured eight times during the study. Dietary pattern, alcohol consumption, smoking habits, drug use, and anthropometric data were also recorded. RESULTS: The changes observed in serum cholesterol concentration between baseline and intervention were not statistically different in all groups. The changes were 0.0 mmol/l (T), +0.01 mmol/l (E) and +0.05 mmol/l (M) for total serum cholesterol; 0 mmol/l (T), -0.02 mmol/l (E) and -0. 03 mmol/l (M) for HDL-C; -0.13 mmol/l (T), +0.02 mmol/l (E) and -0. 05 mmol/l (M) for LDL-C. Serum triglycerides showed a significant increase during intervention (P < 0.01 by ANOVA) in all groups with a change of 0.18 mmol/l, 0.18 mmol/l and 0.22 mmol/l, for tea, espresso and mocha group respectively. CONCLUSIONS: The results indicate that coffee brewed in the Italian way does not alter blood levels of total cholesterol, HDL-cholesterol and LDL-cholesterol, since no significant differences were observed in these blood parameters after a 6-week break from coffee consumption.


Assuntos
Colesterol/sangue , Café , Adulto , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Culinária , Humanos , Itália , Masculino , Chá
16.
J Biol Regul Homeost Agents ; 10(2-3): 54-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9250886

RESUMO

As immune cells are often subjected to hyperthermia that can easily occur either after intense and/or prolonged exercise or during defense against pathogens, in this paper we analysed whether superoxide anion production occurred in lymphocytes exposed to high temperature and, consequently, if antioxidants could exert any protective function. The results demonstrated that an increase of superoxide anion was induced in rabbit lymphocytes exposed to 42 degrees C for 1h, although cell viability was no affected. However, suppression of either Pokeweed mitogen (PWM)-driven cell proliferation, or immunoglobulin production or IL-2 synthesis was observed. To evaluate the capacity of antioxidants to restore the immune suppressed responses, two vitamins, alpha-tocopherol and ascorbic acid, were added to PWM-stimulated cultures following heat treatment. The data demonstrated that alpha-tocopherol was able to totally abrogate the inhibitory effects mediated by thermal stress, while ascorbic acid did not give any protective results.


Assuntos
Ácido Ascórbico/farmacologia , Temperatura Alta , Linfócitos/imunologia , Vitamina E/farmacologia , Animais , Anticorpos/efeitos dos fármacos , Anticorpos/metabolismo , Antioxidantes/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Imunoglobulinas/efeitos dos fármacos , Imunoglobulinas/metabolismo , Interleucina-2/metabolismo , Linfócitos/efeitos dos fármacos , Masculino , Coelhos , Superóxidos/metabolismo
17.
Free Radic Biol Med ; 19(5): 541-52, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8529913

RESUMO

The antioxidant activity of the major phenols derived from hydroxycinnamic acid (caffeic, ferulic, and p-coumaric acids) on in vitro LDL oxidation was screened, using Cu2+ as catalyst. The presence of the second phenolic hydroxy group enhanced the inhibitory effect of these compounds. In fact, at 5 microM concentration, only caffeic acid completely protected LDL from modification as measured as conjugated dienes formation and apo B-100 fragmentation, also preserving alpha-tocopherol. The effect of caffeic acid in inhibiting LDL oxidative modification induced by three different oxidant systems was tested. Using both Cu2+ and 2,2'-azobis (2-amidinopropane)-hydrochloride (AAPH), the inhibitory effect of caffeic acid was dose-dependent. Yet, the better protection was achieved in the metal-ion dependent system. Also the murine macrophages-mediated LDL oxidation was efficiently inhibited by 5 microM caffeic acid. UV-VIS spectra of caffeic acid incubated with cupric ions show the formation of a caffeic acid:copper complex, responsible for a transient chelating activity. This mechanism, coupled with its free radical scavenging property, accounts for the higher inhibitory activity exhibited by caffeic in Cu(2+)-catalyzed reaction.


Assuntos
Antioxidantes/farmacologia , Ácidos Cafeicos/farmacologia , Lipoproteínas LDL/metabolismo , Macrófagos Peritoneais/metabolismo , Análise de Variância , Animais , Células Cultivadas , Cromanos/farmacologia , Humanos , Cinética , Peróxidos Lipídicos/metabolismo , Lipoproteínas LDL/sangue , Lipoproteínas LDL/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade
18.
J Lipid Res ; 35(6): 1085-92, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8077847

RESUMO

Several lines of evidence support a role for oxidized low density lipoprotein (LDL) in the genesis of the atherosclerotic lesion. Hence, the effect of compounds with antioxidant properties on LDL oxidation assumes great significance. Ascorbate, a potent water-soluble chain-breaking antioxidant, has been shown to inhibit LDL oxidation. Aminoguanidine (AMG) is a pharmacological inhibitor of advanced non-enzymatic glycosylation. Recently it has been suggested that aminoguanidine might have an inhibitory effect on LDL oxidation, but total lipid peroxidation assayed by conjugated diene formation was not inhibited. Thus, in this study, we compared the effect of aminoguanidine with ascorbate to obtain a better appreciation of the effect of AMG on Cu(2+)-catalyzed LDL oxidation. Oxidative modification of LDL was monitored by assaying intermediates and end products of lipid peroxidation, conjugated dienes (CD), lipid peroxides (LPO), and relative electrophoretic mobility (REM). Apolipoprotein B-100 modification (increased fluorescence, fragmentation on SDS-PAGE, and 125I-labeled LDL degradation by human macrophages) was also measured. Ascorbate (100 microM) inhibited LDL oxidation by > 95%, as evidenced by all of the selected indices. Aminoguanidine (20 mM) substantially decreased thiobarbituric acid-reactive substances (TBARS) activity and lipid peroxide formation, but only partially prevented the increase of REM (-55%), apoB fluorescence (-39%), and degradation by macrophages (-54%). Unlike ascorbate, AMG failed to preserve alpha-tocopherol in LDL, prevent apoB-100 fragmentation, or inhibit conjugated diene formation during LDL oxidation. Furthermore, incubation of AMG with already oxidized LDL resulted in a significant decrease in TBARS activity and LPO, and 26.9% decrease in the REM of LDL.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácido Ascórbico/farmacologia , Guanidinas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Apolipoproteína B-100 , Apolipoproteínas B/metabolismo , Cobre/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Guanidinas/administração & dosagem , Humanos , Cinética , Macrófagos/metabolismo , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Free Radic Biol Med ; 16(1): 49-55, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8299996

RESUMO

The purpose of this study was to determine the most potent activator of the respiratory burst of polymorphonuclear leukocytes (PMN) with respect to the oxidative modification of low density lipoprotein (LDL). Phorbol-12-myristate-13-acetate (PMA), n-formyl-methionyl-leucylphenylalanine (nFMLP), lipopolysaccharide (LPS), and opsonized zymosan (OZ) were tested. The generation of reactive oxygen species by PMN was assayed as superoxide anion production. Oxidative modification of LDL was monitored by thiobarbituric acid reactive substance (TBARS) activity, by conjugated dienes formation at 234nm and by electrophoretic mobility on agarose gel. PMA was the most potent activator of PMN, inducing a 6-fold increase in the superoxide anion production, followed by OZ (3-fold increase). PMA activation also induced the greatest modification of LDL by PMN: 700% increase of conjugated dienes formation, 222% increase of TBARS, and 70% increase in the electrophoretic mobility. The indices of oxidative modification significantly correlated with the superoxide anion generated by different activators. Also, LDL oxidation by PMN was inhibited by superoxide dismutase but not by catalase, methionine, or hydroxyl radical scavengers. Our data indicate that PMNs activated by PMA produce a mildly oxidized form of LDL by a mechanism that appears to involve the superoxide anion.


Assuntos
Lipoproteínas LDL/sangue , Neutrófilos/metabolismo , Explosão Respiratória/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Proteínas Opsonizantes , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/farmacologia , Superóxidos/sangue , Acetato de Tetradecanoilforbol/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Zimosan/farmacologia
20.
Int J Epidemiol ; 22(5): 855-68, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8282465

RESUMO

The major sources of macronutrients in the Italian diet were assessed. Elderly Italians, aged > or = 60 recorded their weighed intake for a 7-day period. A total of 945 subjects from 14 centres throughout Italy participated during the period 1983-1987. These data were used to quantify the contribution of individual foods to the total intake of and variability in intake of kilocalories, protein, carbohydrate, total fat, saturated fat, oleic acid, polyunsaturated fatty acids, linoleic acid, and cholesterol. The foods ranked one to five for Italy were compared to the top five foods contributing to these nutrients in the diet of the elderly in the US based on the NHANES II Survey (1976-1980). These data provide information for the design of an Italian data-based quantitative food frequency questionnaire. They are also of interest in their description of an industrialized, well-nourished population with a dietary pattern markedly different from the US--lower in saturated fat, higher in complex carbohydrate and higher in alcohol.


Assuntos
Inquéritos sobre Dietas , Gorduras na Dieta/administração & dosagem , Comportamento Alimentar , Idoso , Comparação Transcultural , Ingestão de Energia , Feminino , Alimentos , Humanos , Itália/epidemiologia , Masculino , Estados Unidos/epidemiologia
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