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HEALTH

1. Eur J Intern Med. 2003 Oct;14(6):361-366.

Red wine and red wine polyphenolic compounds but not alcohol inhibit ADP-induced platelet aggregation.

De Lange DW, Van Golden PH, Scholman WL, Kraaijenhagen RJ, Akkerman JW, Van De Wiel A.

Department of Internal Medicine, Meander Medical Center, PO Box 1502, 3800 BM Amersfoort, The Netherlands.

Background: Moderate alcohol consumption reduces the risk of cardiovascular diseases, especially coronary heart disease (CHD). Because of the presence of polyphenols in red wine, this type of beverage may be superior to other alcoholic drinks in the prevention of CHD. Inhibition of platelet aggregation is thought to be one of the mechanisms underlying this favorable effect. The present study analyzes the direct effect of alcohol and red wine polyphenols on platelet aggregation. Methods: Unfractionated red wine, a red wine polyphenolic extract, and alcohol were added in different concentrations to a standardized quantity of blood platelets 2 min before aggregation was induced by different concentrations of ADP. Aggregation was measured in an aggregometer and results were compared to a control 0.9% NaCl solution. Results: Alcohol in concentrations up to 0.24 percent did not inhibit platelet aggregation in vitro initiated with ADP The polyphenolic red wine extract inhibited aggregation dose-dependently and significantly from concentrations of 45 mg/l ( [Formula: see text] ) or more. Red wine only inhibited platelet aggregation at very high concentrations ( approximately 0.24 and 0.48 alcohol%). Conclusions: Consumption of red wine has an inhibitory effect on platelet aggregation, which is caused by the polyphenolic compounds in the wine. Alcohol itself does not have a direct inhibitory effect within a range up to 0.24 percent. Since this effect is only observed at very high concentrations, it is unlikely to be of clinical relevance in a moderate drinking pattern. The results do not exclude platelet inhibition by wine in vivo. However, this must be related to metabolic changes rather than to direct blockade.

2: Xenobiotica. 2000 Nov;30(11):1047-54.

Glucuronidation of resveratrol, a natural product present in grape and wine, in the human liver.

de Santi C, Pietrabissa A, Mosca F, Pacifici GM.

Department of Neurosciences, Section of Pharmacology, Medical School, Via Roma 55, I-56126 Pisa, Italy.

1. Resveratrol, a polyphenolic compound present in grape and wine, has beneficial effects against cancer and protective effects on the cardiovascular system. It has been shown that the compound is sulphated in human liver and the aims of the present investigation were to study resveratrol glucuronidation in human liver microsomes and to determine whether flavonoids inhibit resveratrol glucuronidation. 2. A simple and reproducible radiometric assay for resveratrol glucuronidation was developed. The assay employed uridine-5'-diphosphoglucuronic acid-[14C] and unlabelled resveratrol. Resveratrol-glucuronide was isolated by TLC. The intra- and interassays variabilities were 1 and 1.5%, respectively. 3. The rate of resveratrol glucuronidation was measured in 10 liver samples. The mean +/- SD and median of resveratrol glucuronidation rate were 0.69 +/- 0.34 and 0.80 nmol/min/mg, respectively. Resveratrol glucuronosyl transferase followed Michaelis-Menten kinetics and the Km and Vmax (mean +/- SD; n = 5) were 0.15 +/- 0.09 mM and 1.3 +/- 0.3 nmol/min/mg, respectively. The intrinsic clearance was 11 +/- 4 x 10(-3) ml/min.mg. 4. The flavonoid quercetin inhibited resveratrol glucuronidation and its IC50 (mean +/- SD; n = 3) was 10 +/- 1 microM. Myricetin, catechin, kaempferol, fisetin and apigenin (all at 20 microM) inhibited resveratrol glucuronidation and the percent of control ranged between 46% (catechin) to 72% (apigenin). 5. The present results show that resveratrol is glucuronated in the human liver. Glucuronidation may reduce the bioavailability of this compound however, flavonoids inhibit resveratrol glucuronidation and such an inhibition might improve the bioavailability of resveratrol.


3. Xenobiotica. 2000 Jun;30(6):609-17.
Sulphation of resveratrol, a natural product present in grapes and wine, in the human liver and duodenum.

De Santi C, Pietrabissa A, Spisni R, Mosca F, Pacifici GM.

Department of Neurosciences, Medical School, Pisa, Italy.

1. Resveratrol, a polyphenolic compound present in grapes and wine, has beneficial effects against cancer and protective effects on the cardiovascular system. It is present in the diet, and the hepatic and duodenal sulphation might limit the bioavailability of this compound. The aim was to study the sulphation of resveratrol in the human liver and duodenum. 2. A simple and reproducible radiometric assay for resveratrol sulphation was developed. It employed 3'-phosphoadenosine-5'-phosphosulphate-[35S] as the sulphate donor and the rates of resveratrol sulphation (mean +/- SD, pmol/min/mg cytosolic protein) were 90 +/- 21 (liver, n = 10) and 74 +/- 60 (duodenum, n = 10, p = 0.082). 3. Resveratrol sulphotransferase followed Michaelis-Menten kinetics and Km (mean +/- SD; microM) was 0.63 +/- 0.03 (liver, n = 5) and 0.50 +/- 0.26 (duodenum, n = 5, p = 0.39) and Vmax (mean +/- SD, pmol/min/mg cytosolic protein) were 125 +/- 31 (liver, n = 5) and 129 +/- 85 (duodenum, n = 5, p = 0.62). 4. Resveratrol sulphation was inhibited by the flavonoid quercetin, by mefenamic acid and salicylic acid, two commonly used non-steroidal anti-inflammatory drugs. IC50 of resveratrol sulphation for quercetin was 12 +/- 2 pM (liver) and 15 +/- 2 pM (duodenum), those for mefenamic acid were 24 +/- 3 nM (liver) and 11 +/- 0.6 nM (duodenum), and those for salicylic acid were 53 +/- 9 microM (liver) and 66 +/- 4 microM (duodenum). 5. The potent inhibition of resveratrol sulphation by quercetin, a flavonoid present in wine, fruits and vegetables, suggests that compounds present in the diet may inhibit the sulphation of resveratrol, thus improving its bioavailability.

 

4. Drugs Exp Clin Res. 1998;24(3):133-8.

Plasma and tissue resveratrol concentrations and pharmacological activity.

Bertelli A, Bertelli AA, Gozzini A, Giovannini L.

Department of Medical Pharmacology, Chemotherapy and Toxicology, University of Milan, Italy.

In this study a comparison was made between results obtained from resveratrol dosages which have been shown to be pharmacologically active, in vitro and in vivo, and the results of plasma and tissue concentrations obtained after a single administration or after prolonged administration of red wine with a known resveratrol content. The dosages used by different investigators in the tests are very different and, in general, rather high in relation to the concentrations which are found in wine or grapes. The results of our tests on platelet aggregation confirm that even with modest dosages of resveratrol, a pharmacological effect can be observed, and that these dosages can be compatible with the resveratrol concentrations obtained after oral administration. The data obtained from these tests on animals can lead to the conclusion that even an average drinker of wine can, particularly in the long term, absorb a sufficient quantity of resveratrol to explain the beneficial effect of red wine on health, which has been observed in epidemiological studies carried out in populations whose daily diet includes the drinking of wine.

5. Drugs Exp Clin Res. 1998;24(1):51-5.
Evaluation of kinetic parameters of natural phytoalexin in resveratrol orally administered in wine to rats.

Bertelli AA, Giovannini L, Stradi R, Urien S, Tillement JP, Bertelli A.

Institute of Anatomy, University of Milan, Milan, Italy.

In view of the increasing interest in the biological activity of resveratrol, one of the components of red wine which is considered to be one of the main ingredients responsible for the beneficial effect of wine on human health, we have studied plasma kinetics and tissue bioavailability of this compound after red wine oral administration in rats. Plasma pharmacokinetics after oral administration of resveratrol could be described by an open one- or two-compartment model. Tissue concentrations show a significant cardiac bioavailability, and a strong affinity for the liver and kidneys.

 

6. Clin Biochem. 2001 Jul;34(5):415-20.

Do wine polyphenols modulate p53 gene _expression in human cancer cell lines?

Soleas GJ, Goldberg DM, Grass L, Levesque M, Diamandis EP.

Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.

BACKGROUND: The p53 gene is an established tumor suppressor and an inducer of apoptosis. We here attempt to determine whether the putative anticarcinogenic properties attributed to red wine and its polyphenolic constituents depend, at least in part, upon their ability to modulate p53 _expression in cancer cells.

METHODS: Three human breast cancer cell lines (MCF-7, T47D; MDA-MB-486) and one human colon cancer cell line [Colo 320 HSR (+)] were treated for 24-h with each of four polyphenols [quercetin; (+)-catechin, trans-resveratrol; caffeic acid] at concentrations ranging from 10(-7) M to 10(-4) M, after which, p53 concentrations were measured in cell lysates by a time-resolved fluorescence immunoassay.

RESULTS: None of the polyphenols tested affected p53 _expression in the breast cancer cell lines T-47D and MDA-MB-486. p53 content of MCF-7 breast cancer cells (wild-type) was increased by caffeic acid, decreased by resveratrol, and showed a twofold increase with catechin, that reached borderline statistical significance; however, none of these effects were dose-responsive. Colo 320 HSR (+) cells (with a mutant p53 gene) had lower p53 content upon stimulation, reaching borderline statistical significance, but without being dose-responsive, in the presence of caffeic acid and resveratrol. Apart from toxicity at 10(-4) M, quercetin had no effect upon these four cell lines.

CONCLUSIONS: The observed p53 concentration changes upon stimulation by polyphenols are relatively small, do not follow a uniform pattern in the four cell lines tested, and do not exhibit a dose-response effect. For these reasons, we speculate that the putative anticarcinogenic properties of wine polyphenols are unlikely to be mediated by modulation of p53 gene _expression.




 

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