How grapes protect against heart disease
The colour and the slight harshness in red wine come from a natural substance that can combat cardiovascular disease. White wine and alcohol-free grape juice can also have positive effects, according to a laboratory study at Linköping University.
The fact that drinking wine in moderation can protect against heart disease is well documented, but the mechanism behind it is unknown so far. Pharmacology researcher Ingrid Persson wanted to test the hypothesis that a chemical in the wine affects the enzyme ACE, which plays a major role in high blood pressure. Using a medicine that inhibits this enzyme is often the first measure against heart disease.
In the study, which is published in the International Journal of Nutrition, Pharmacology, Neurological Diseases, cultivated cells from human umbilical cords were used to investigate how different drinks affect ACE activity. The cells were steeped in red, white and rosé wine, grape juice and resveratrol, a dietary supplement that is extracted from grapes and is marketed as helpful against heart problems. 13 % ethanol was used as a control. After ten minutes at 37 degrees, the results were analysed.
All the varieties of wine tested, regardless of colour, and the non-alcoholic red grape juice brought about a significant reduction in enzyme activity. The white grape juice, the dietary supplement resveratrol and the ethanol, however, had no effect.
Persson concludes that it is the contents of the flavonoids – the generic term for a group of chemicals present in for instance grapes – that causes the inhibiting of the enzyme, not the alcohol.
Flavonoid content in grapes varies depending on the colour and variety, soil, climate and geographical origin. Production methods of wine and grape juice are also significant.
Umbilical cord cells were used with the consent of the respective mothers. Ingrid Persson is currently senior lecturer in biomedical science at Karlstad University.
Article: Red wine, white wine, rosé wine, and grape juice inhibit angiotensin-converting enzyme in human endothelial cells by Ingrid Persson. Int J Nutr Pharmacol Neurol Dis online 25 feb 2013. DOI: 10.4103/2231-0738.106975
Last updated: 2013-04-04