Single and repeated moderate consumption of native or dealcoholized red wine show different effects on antioxidant parameters in blood and DNA strand breaks in peripheral leukocytes in healthy volunteers: a randomized controlled trial [ISRCTN68505294]
1 Department of Hemostasis and Transfusion Medicine, School of Medicine, University of Duesseldorf, Moorenstr. 5, 40225 Duesseldorf, Germany
2 Institute for Medical Biometry, Informatics and Epidemiology, University Hospital of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
3 Department of General Internal Medicine, University Hospital of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
4 Institute for Medical Radiobiology, University Duisburg-Essen, 45122 Essen, Germany
5 Institute for Molecular Biotechnology, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany
Nutrition Journal 2005, 4:33 doi:10.1186/1475-2891-4-33Published: 14 November 2005
Red wine (RW) is rich in antioxidant polyphenols that might protect from oxidative stress related diseases, such as cardiovascular disease and cancer. Antioxidant effects after single ingestion of RW or dealcoholized RW (DRW) have been observed in several studies, but results after regular consumption are contradictory. Thus, we examined if single or repeated consumption of moderate amounts of RW or DRW exert antioxidant activity in vivo.
Total phenolic content and concentration of other antioxidants in plasma/serum, total antioxidant capacity (TEAC) in plasma as well as DNA strand breaks in peripheral leukocytes were measured in healthy non-smokers A) before, 90 and 360 min after ingestion of one glass of RW, DRW or water; B) before and after consumption of one glass of RW or DRW daily for 6 weeks. DNA strand breaks (SB) were determined by single cell gel electrophoresis (Comet Assay) in untreated cells and after induction of oxidative stress ex vivo with H2O2 (300 μM, 20 min).
Both RW and DRW transiently increased total phenolic content in plasma after single consumption, but only RW lead to a sustained increase if consumed regularly. Plasma antioxidant capacity was not affected by single or regular consumption of RW or DRW. Effects of RW and DRW on DNA SB were conflicting. DNA strand breaks in untreated cells increased after a single dose of RW and DRW, whereas H2O2 induced SB were reduced after DRW. In contrast, regular RW consumption reduced SB in untreated cells but did not affect H2O2 induced SB.
The results suggest that consumption of both RW and DRW leads to an accumulation of phenolic compounds in plasma without increasing plasma antioxidant capacity. Red wine and DRW seem to affect the occurrence of DNA strand breaks, but this cannot be referred to antioxidant effects.