Effect of polyphenol-rich grape seed extract on ambulatory blood pressure in subjects with pre- and stage I hypertension

• Published in: British journal of nutrition Vol. 110; no. 12; pp. 2234 - 2241
• Main Authors: Ras, Rouyanne T., Zock, Peter L., Zebregs, Yvonne E. M. P., Johnston, Neil R., Webb, David J., Draijer, Richard
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 28.12.2013
• Subjects: antihypertensive effect; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Blood and lymphatic vessels; Blood pressure; Blood Pressure - drug effects; blood sampling; Cardiology. Vascular system; Cellulose; Dietary supplements; endothelins; Experimental diseases; fasting; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; grape seed extract; grapes; Human and Clinical Nutrition; Humans; Hypertension; Hypertension - drug therapy; Hypertension - physiopathology; Male; Medical sciences; Metabolites; Middle Aged; nitric oxide; placebos; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; platelet aggregation; Polyphenols; Polyphenols - pharmacology; Polyphenols - therapeutic use; Prehypertension - drug therapy; Prehypertension - physiopathology; renin; Seeds - chemistry; urine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitis - chemistry; Dietary intervention studies; Blood pressure; Grape seed extract; Cardiovascular health; Human; Hypertension; Seeds; Fruit; Nutrition; Health; Cardiovascular disease; Extract; Micronutrient; Polyphenol; Grape; Proanthocyanidin; Hemodynamics; Ambulatory
• ISSN: 0007-1145; 1475-2662; 1475-2662
• DOI: 10.1017/S000711451300161X

Dietary polyphenols, such as those from grape products, may exert beneficial effects on cardiovascular health, including anti-hypertensive effects. We investigated the effect of a specific grape seed extract (GSE) rich in low-molecular-weight polyphenolic compounds on ambulatory blood pressure (ABP) in untreated subjects with pre- and stage I hypertension. In addition, potential mechanisms that could underlie the hypothesised effect of GSE on blood pressure (BP), and platelet aggregation, were explored. The study was designed as a double-blind, placebo-controlled, randomised, parallel-group intervention study including seventy healthy subjects with systolic BP between 120 and 159 mmHg. A 1-week run-in period was followed by an 8-week intervention period, during which subjects consumed capsules containing either 300 mg/d of GSE or a placebo (microcrystalline cellulose). Before and after the intervention, daytime ABP readings, 24 h urine samples and fasting and non-fasting blood samples were taken. The mean baseline systolic BP was 135·8 (se 1·3) mmHg and diastolic BP was 81·5 (se 0·9) mmHg. BP values were modestly, but not significantly, affected by the polyphenol-rich GSE treatment v. placebo with an effect of − 3·0 mmHg for systolic BP (95 % CI − 6·5, 0·5) and − 1·4 mmHg for diastolic BP (95 % CI − 3·5, 0·6). Vasoactive markers including endothelin-1, NO metabolites and asymmetric dimethylarginine, plasma renin activity and platelet aggregation were not affected by the GSE intervention. Our findings show that consumption of polyphenol-rich GSE does not significantly lower ABP in untreated subjects with pre- and stage I hypertension.