%0 Journal Article
%T Effects of Dietary Nitrates on Systemic and Cerebrovascular Hemodynamics
%A Vernon Bond Jr.
%A Bryan H. Curry
%A Richard G. Adams
%A M. Sadegh Asadi
%A Richard M. Millis
%A Georges E. Haddad
%J Cardiology Research and Practice
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/435629
%X Cerebral blood flow dysregulation is often associated with hypertension. We hypothesized that a beetroot juice (BRJ) treatment could decrease blood pressure and cerebrovascular resistance (CVR). We subjected 12 healthy females to control and BRJ treatments. Cerebrovascular resistance index (CVRI), systolic blood pressure (SBP), total vascular resistance (TVR), and the heart rate-systolic pressure product (RPP) measured at rest and at two exercise workloads were lower after the BRJ treatment. CVRI, SBP, and RPP were lower without a lower TVR at the highest exercise level. These findings suggest improved systemic and cerebral hemodynamics that could translate into a dietary treatment for hypertension. 1. Introduction Cognitive deficits are associated with dysregulation of cerebral blood flow in a wide variety of disease states [1¨C10]. Decreased cerebral blood flow from stroke is a prevalent complication of cardiovascular disease associated with atherosclerosis and hypertension [8]. Although it is controversial whether obesity is a disease, overweight individuals are susceptible to diabetes mellitus and most of the aforementioned cardiovascular abnormalities, defined as metabolic syndrome, also producing predilections for brain hypoperfusion [11]. In that regard, we have previously reported a predilection for decreased middle cerebral artery blood flow velocity associated with an exaggerated vasopressor response to aerobic exercise in overweight, otherwise healthy, young adult African-American university students [12]. Retired professional NFL football players with large body mass index and waist/hip ratio also seem to be at high risk for low cerebral blood flow, associated with cognitive impairment [6]. Dietary nitrate supplementation is purported to be an efficacious adjunctive treatment that decreases blood pressure [13] by the mechanism of decreasing peripheral vascular resistance [14] and may, therefore, be useful as a counter measure against brain hypoperfusion by decreasing cerebrovascular resistance. However, no studies have addressed the effects of nitrate supplementation on blood pressure-flow indexes of brain perfusion. Therefore, we designed this study to test the hypothesis that dietary nitrate supplementation with beetroot juice may increase middle cerebral artery blood flow velocity and may decrease a Doppler ultrasonographic index of cerebrovascular resistance in healthy young adult African-American female university students. 2. Methods This study used a crossover design where participants were randomly assigned to receive either a placebo
%U http://www.hindawi.com/journals/crp/2013/435629/