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1.
Am J Physiol Heart Circ Physiol ; 298(6): H2226-31, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20418480

RESUMEN

In healthy subjects a standard drink of either red wine (RW) or ethanol (EtOH) has no effect on muscle sympathetic nerve activity or on heart rate (HR), whereas two drinks increase both. Using time- and frequency-domain indexes of HR variability (HRV), we now tested in 12 subjects (24-47 yr, 6 men) the hypotheses that 1) this HR increase reflects concurrent dose-related augmented sympathetic HR modulation and 2) RW with high-polyphenol content differs from EtOH in its acute HRV effects. RW, EtOH, and water were provided on 3 days, 2 wk apart according to a randomized, single-blind design. Eight-minute segments were analyzed. One alcoholic drink increased blood concentrations to 36 + or - 2 mg/dl (mean + or - SE), and 2 drinks to 72 + or - 4 (RW) and 80 + or - 2 mg/dl (EtOH). RW quadrupled plasma resveratrol (P < 0.001). HR fell after both water drinks. When compared with respective baselines, one alcoholic drink had no effect on HR or HRV, whereas two glasses of both increased HR (RW, +5.4 + or - 1.2; and EtOH, +5.7 + or - 1.2 min(-1); P < 0.001), decreased total HRV by 28-33% (P < 0.05) and high-frequency spectral power by 32-42% (vagal HR modulation), and increased low-frequency power by 28-34% and the ratio of low frequency to high frequency by 98-119% (sympathetic HR modulation) (all, P < or = 0.01). In summary, when compared with water, one standard drink lowered time- and frequency-domain markers of vagal HR modulation. When compared with respective baselines, two alcoholic drinks increased HR by diminished vagal and augmented sympathetic HR modulation. Thus alcohol exerts dose-dependent HRV responses, with RW and EtOH having a similar effect.


Asunto(s)
Etanol/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Vino , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Corazón/inervación , Corazón/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Método Simple Ciego , Sistema Nervioso Simpático/efectos de los fármacos , Sistema Nervioso Simpático/fisiología
2.
Am J Physiol Heart Circ Physiol ; 294(2): H605-12, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18055508

RESUMEN

The cardiovascular benefits of light to moderate red wine consumption often have been attributed to its polyphenol constituents. However, the acute dose-related hemodynamic, vasodilator, and sympathetic neural effects of ethanol and red wine have not been characterized and compared in the same individual. We sought to test the hypotheses that responses to one and two alcoholic drinks differ and that red wine with high polyphenol content elicits a greater effect than ethanol alone. Thirteen volunteers (24-47 yr; 7 men, 6 women) drank wine, ethanol, and water in a randomized, single-blind trial on three occasions 2 wk apart. One drink of wine and ethanol increased blood alcohol to 38 +/- 2 and 39 +/- 2 mg/dl, respectively, and two drinks to 72 +/- 4 and 83 +/- 3 mg/dl, respectively. Wine quadrupled plasma resveratrol (P < 0.001) and increased catechin (P < 0.03). No intervention affected blood pressure. One drink had no heart rate effect, but two drinks of wine increased heart rate by 5.7 +/- 1.6 beats/min; P < 0.001). Cardiac output fell 0.8 +/- 0.3 l/min after one drink of ethanol and wine (both P < 0.02) but increased after two drinks of ethanol (+0.8 +/- 0.3 l/min) and wine (+1.2 +/- 0.3 l/min) (P < 0.01). One alcoholic drink did not alter muscle sympathetic nerve activity (MSNA), while two drinks increased MSNA by 9-10 bursts/min (P < 0.001). Brachial artery diameter increased after both one and two alcoholic drinks (P < 0.001). No beverage augmented, and the second wine dose attenuated (P = 0.02), flow-mediated vasodilation. One drink of ethanol dilates the brachial artery without activating sympathetic outflow, whereas two drinks increase MSNA, heart rate, and cardiac output. These acute effects, which exhibit a narrow dose response, are not modified by red wine polyphenols.


Asunto(s)
Arterias/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Depresores del Sistema Nervioso Central/farmacología , Etanol/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Vino , Adulto , Arginina Vasopresina/sangre , Arterias/anatomía & histología , Factor Natriurético Atrial/sangre , Arteria Braquial/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiología , Femenino , Flavonoides/análisis , Flavonoides/farmacología , Humanos , Masculino , Persona de Mediana Edad , Sistemas Neurosecretores/efectos de los fármacos , Norepinefrina/sangre , Fenoles/análisis , Fenoles/farmacología , Polifenoles , Método Simple Ciego , Resistencia Vascular/efectos de los fármacos , Vino/análisis
3.
Clin Biochem ; 36(1): 79-87, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12554065

RESUMEN

BACKGROUND: Despite their powerful biologic activities conducive to protection against atherosclerosis, cancer and inflammatory diseases demonstrated in vitro, there is considerable doubt whether the polyphenolic constituents present in red wine and other dietary components are effective in vivo. OBJECTIVE: We have tested the absorptive efficiency of three of these constituents (trans-resveratrol, [+]-catechin and quercetin) when given orally to healthy human subjects in three different media. DESIGN: Twelve healthy males aged 25 to 45 were randomly assigned to three different groups consuming orally one of the following polyphenols: trans-resveratrol, 25 mg/70 kg; [+]-catechin 25 mg/70 kg; quercetin 10 mg/70 kg. Each polyphenol was randomly administered at 4-week intervals in three different matrices: white wine (11.5% ethanol), grape juice, and vegetable juice/homogenate. Blood was collected at zero time and at four intervals over the first four hours after consumption; urine was collected at zero time and for the following 24-h. The sums of free and conjugated polyphenols were measured in blood serum and urine by a gas-chromatographic method. RESULTS: All three polyphenols were present in serum and urine predominantly as glucuronide and sulfate conjugates, reaching peak concentrations in the former around 30-min after consumption. The free polyphenols accounted for 1.7 to 1.9% (trans-resveratrol), 1.1 to 6.5% ([+]-catechin) and 17.2 to 26.9% (quercetin) of the peak serum concentrations. The absorption of trans-resveratrol was the most efficient as judged by peak serum concentration, area-under-the curve (4 h) and urinary 24-h excretion (16-17% of dose consumed). [+]-Catechin was the poorest by these criteria (urine 24-h excretion 1.2%-3.0% of dose consumed), with quercetin being intermediate (urine 24-h excretion 2.9%-7.0% of dose consumed). Some significant matrix effects were observed for the serum polyphenol concentrations, but in the case of urine no matrix promoted significantly higher excretion than the other two. CONCLUSIONS: The absorption of these three polyphenols is broadly equivalent in aqueous and alcoholic matrices but, at peak concentrations of 10 to 40 nmol/L, is inadequate to permit circulating concentrations of 5 to 100 micromol/L consistent with in vitro biologic activity. The voluminous literature reporting powerful in vitro anticancer and antiinflammatory effects of the free polyphenols is irrelevant, given that they are absorbed as conjugates.


Asunto(s)
Flavonoides , Fenoles/metabolismo , Polímeros/metabolismo , Vino , Administración Oral , Adulto , Antioxidantes/farmacocinética , Catequina/farmacocinética , Cromatografía de Gases , Glucosa/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Modelos Químicos , Fenoles/sangre , Fenoles/orina , Quercetina/farmacocinética , Resveratrol , Estilbenos/farmacocinética , Factores de Tiempo
4.
Clin Biochem ; 35(2): 119-24, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11983346

RESUMEN

BACKGROUND: There has been growing interest in the analysis of certain polyphenols in wine, especially flavonoids, trihydroxystilbenes and phenolic acids, stimulated by intense research into their potential benefits to human health. One of their main properties in this regard is their antioxidant activity, which enables them to attenuate the development of atherosclerosis, inflammatory diseases, and cancer. METHODS: A two stage CD-1 mouse skin cancer model using 9,10-dimethyl-1,2-benzanthracene (DMBA) as initiator and phorbol 12-myristate 13-acetate (TPA) as promoter was employed to compare the antitumorigenic activities of one polyphenol from each of four different classes: flavanols [(+)-catechin], stilbenes (trans-resveratrol), flavonols (quercetin) and hydroxybenzoic acids (gallic acid). Animals were treated with specific polyphenols at doses ranging from 0 to 25 micromoles (dissolved in 200 microL acetone), twice a week for eighteen weeks. The solution was applied topically to the shaved dorsal region of each animal. The relative potencies of the polyphenols were compared by evaluating the percentage inhibition of tumor formation in individual mice and the number of mice developing one or more tumors with the different dose schedules. RESULTS: Probit analysis revealed that quercetin was the most (ED(50)<1 micromole) and gallic acid the least effective (ED(50) 5-10 micromoles). (+)-Catechin and trans-resveratrol were intermediate, with ED(50) values of 5 and 6 micromoles, respectively. CONCLUSION: We have shown recently that trans-resveratrol is absorbed much more efficiently than (+)-catechin and quercetin in humans after oral consumption. Taking this and the relative concentrations in red wine into account, together with the present results, we conclude that trans-resveratrol may be the most effective anticancer polyphenol present in red wine as consumed po by healthy human subjects.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Catequina/farmacología , Flavonoides , Ácido Gálico/farmacología , Quercetina/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Estilbenos/farmacología , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Animales , Ratones , Fenoles/farmacología , Polímeros/farmacología , Resveratrol , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol/toxicidad , Vino
5.
J Agric Food Chem ; 50(5): 1032-9, 2002 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-11853476

RESUMEN

To investigate the role of trichloro compounds as a potential cause of "cork taint" in wine, an assay for trichloroanisole (TCA) and trichlorophenol (TCP) in corks and wine was developed utilizing solid phase extraction on a C(18) cartridge followed by gas chromatography with mass selective detection. Recovery and imprecision for TCA were 86-102 and 1.6-5.8%, respectively, and for TCP 82-103% and 1.7-3.9%, respectively. Limits of detection and quantitation were 0.1 and 2 ng/L, respectively, for TCA, and 0.7 and 4 ng/L, respectively for TCP. A survey of 2400 commercial wines revealed a higher incidence of cork taint in white wine than in red and in wines utilizing composite cork closures; wines from central Europe and Spain had higher overall rates of contamination and those from Canada and Italy the lowest. Significant but modest associations were found between the TCA and TCP contents of the wines and corks, but many wines exhibiting cork taint had low or undetectable concentrations of TCA. Over a 12-month period, experimentally bottled wines exhibited a slow increase in TCA and TCP content while cork closures manifested a decrease; most bottles showing cork taint contained low levels of TCA, and TCP concentrations were well below the sensory threshold. Neither compound was cytotoxic to human cell lines in culture up to final concentrations of 500 ng/mL. It was concluded that these two trichloro compounds are, at most, minor components of cork taint in commercial wines.


Asunto(s)
Cloroacetatos , Contaminación de Alimentos , Ácido Tricloroacético/análisis , Vino/análisis , Análisis de Varianza , Cromatografía Líquida de Alta Presión , Manipulación de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Fenoles/análisis
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