Beneficial effects of acute trans-resveratrol supplementation in treated hypertensive patients with endothelial dysfunction

Endothelial dysfunction is a surrogate marker of cardiovascular risk. Resveratrol is known to improve endothelial function in animals, however, clinical trials are limited. We hypothesized that the acute trans-resveratrol supplementation improves endothelial function in treated hypertensive patients with endothelial dysfunction. Twenty-four hypertensive patients between 45 and 65 years-old with baseline endothelial dysfunction were enrolled in a randomized, cross-over, double-blind, placebo-controlled trial. Individuals received either a single dose of trans-resveratrol (300 mg) or placebo and were crossed-over after a one-week washout period. Blood pressure (BP) measurements, aortic systolic blood pressure (SBP) and brachial flow-mediated dilation (FMD) were performed before and 1.5 hours after the intervention. FMD was significantly increased in women (4.2 ± 0.5 vs 7.1 ± 1.3%, p = 0.026) but not in men (4.4 ± 0.9 vs 4.9 ± 0.8%, p = 0.588) in the trans-resveratrol group. There was no statistical difference between baseline and final values of brachial BP and also no changes in aortic SBP. Patients with higher low-density lipoprotein (LDL) cholesterol had better FMD response to trans-resveratrol than patients with lower LDL cholesterol (7.4 ± 1.2 vs 4.3 ± 1.0%, p = 0.004). Our study demonstrated that the acute supplementation of trans-resveratrol promoted an improvement in endothelial function, especially in women and those with higher LDL-cholesterol, despite no changes in BP. List of Abbreviation: Aix: augmentation index; AP: augmentation pressure; BP: blood pressure; BMI: body Mass Index; CVD: cardiovascular disease; FMD: flow-mediated dilation; FRS: Framingham Risk Score; HDL: high-density lipoprotein; LDL: low-density lipoprotein; NO: nitric oxide; SPSS: Statistical Package for Social Sciences; ROS: reactive oxygen species; SBP: systolic blood pressure; TG: triglycerides

Stable red cell mass despite contracted plasma volume in men with essential hypertension

Red blood cell mass, plasma volume, and renal and systemic hemodynamic measurements were evaluated in 24 normotensive men (group 1), 45 men with mild essential hypertension (group 2), and 43 men with moderate to severe essential hypertension (group 3). Despite significant hemodynamic differences between the groups and although plasma volume was contracted, the increased hematocrit in the third group of patients was not explained by an increase in red blood cell mass. Because this was the case in all groups it demonstrates that the increased hematocrit in patients with more severe essential hypertension is solely attributable to the contracted plasma volume