Effects of Grape Seed Proanthocyanidin Extract on Vascular Endothelial Function in Participants with Prehypertension: A Randomized, Double-Blind, Placebo-Controlled Study

• Main Authors: Tamami Odai, Masakazu Terauchi, Kiyoko Kato, Asuka Hirose, Naoyuki Miyasaka
• Format: Article
• Language: English
• Published: MDPI AG 2019-11-01
• Series: Nutrients
• Subjects: flow-mediated dilation; hypertension; vascular elasticity; vascular stiffness; polyphenols; flavonoids
• Online Access: https://www.mdpi.com/2072-6643/11/12/2844

This study aimed to investigate the effects of grape seed proanthocyanidin extract (GSPE) on blood pressure and vascular endothelial function in middle-aged Japanese adults with prehypertension. We conducted a randomized, double-blind, placebo-controlled study on 6 men and 24 women aged 40&#8722;64 years old. The participants were randomized to receive tablets containing either low-dose (200 mg/day) or high-dose (400 mg/day) GSPE, or placebo, for 12 weeks. Systolic and diastolic blood pressures (SBP and DBP, respectively), brachial flow-mediated dilation (FMD), and other cardiovascular parameters were measured before and after 4, 8, and 12 weeks of treatment. The mean SBP in the high-dose group significantly decreased by 13 mmHg after 12 weeks (<i>P</i> = 0.028), although FMD did not change. In an ad hoc analysis of non-smoking participants (<i>n</i> = 21), the mean SBP, DBP, stiffness parameter &#946;, distensibility, incremental elastic modulus (Einc), and pulse wave velocity (PWV) also significantly improved in the high-dose group after 12 weeks. Changes in Einc and PWV from baseline to 12 weeks were significantly greater in the high-dose group than in the placebo group (Einc, <i>P</i> = 0.023; PWV, <i>P</i> = 0.03). GSPE consumption could help maintain vascular elasticity and normal blood pressure in this population.