Epidemiological studies beginning in the 1990s have reported that intake of quercetin, a polyphenolic flavonoid found in a wide variety of plant-based foods, such as apples, onions, berries, and red wine, is inversely related to cardiovascular disease. More recent work using hypertensive animals and humans (>140 mm Hg systolic and >90 mm Hg diastolic) indicates a decrease in blood pressure after quercetin supplementation. A number of proposed mechanisms may be responsible for the observed blood pressure decrease such as antioxidant effects, inhibition of angiotensin-converting enzyme activity, and improved endothelium-dependent and -independent function. The majority of these mechanisms have been identified using animal models treated with quercetin, and relatively few have been corroborated in human studies. The purpose of this review is to examine the evidence supporting the role of quercetin as a potential therapeutic agent and the mechanisms by which quercetin might exert its blood pressure-lowering effect.

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Quercetin is a polyphenolic flavonoid. Common sources in the diet are apples, onions, berries, and red wine. Epidemiological studies have found an inverse relationship between dietary quercetin intake and cardiovascular disease. This has led to in vitro, in vivo, and clinical research to determine the mechanism by which quercetin exerts cardio-protective effects. Recent studies have found a reduction in blood pressure when hypertensive (>140 mm Hg systolic and >90 mm Hg diastolic) animals and humans are supplemented with quercetin. Proposed mechanisms for the antihypertensive effect of quercetin include decreased oxidative stress, inhibition of angiotensin converting enzyme activity, improved endothelial function, direct action on the vascular smooth muscle, and/or modulation in cell signaling and gene expression. Although in vitro and in vivo evidence exists to support and refute each possibility, it is likely that quercetin influences multiple targets via a combination of known and as yet undiscovered mechanisms. The purpose of this review is to examine the mechanisms whereby quercetin might reduce blood pressure in hypertensive individuals.

BackgroundClinical studies have reported hydrogen-rich water (HRW) to have therapeutic and ergogenic effects. The aim of this study was to determine the effect of acute supplementation with HRW on exercise performance as measured by VO2, respiratory exchange ratio (RER), heart rate (HR), and respiratory rate (RR).MethodsBaseline levels of all exercise indices were determined in nineteen (4 female, 23.4 ± 9.1 yr; 15 male, 30.5 ± 6.8 yr) healthy subjects using a graded treadmill exercise test to exhaustion. Each subject was examined two additional times in a randomized double-blinded, placebo-controlled crossover fashion. Subjects received either HRW or placebo, which was consumed the day before and the day of the testing. HRW was delivered using the hydrogen-producing tablets, DrinkHRW (5 mg of H2). All data was analyzed with SPSS using pairwise comparisons with Bonferroni adjustment.ResultsHRW supplementation did not influence maximal or minimal indices of exercise performance (VO2, RER, HR and RR) (p < 0.05). However, HRW significantly decreased average exercising RR and HR (p < 0.05). HRW decreased exercising HR during minutes 1–9 of the graded exercise test (121 ± 26 bpm) compared to placebo (126 ± 26 bpm) and baseline (124 ± 27 bpm) (p < 0.001) without substantially influencing VO2.ConclusionAcute supplementation of DrinkHRW tablets may benefit submaximal aerobic exercise performance by lowering exercising HR. Further studies are needed to determine the influence and practical significance of HRW on varying exercise intensities as well as optimal dosing protocols and the effects of chronic use.

BackgroundConcussive events frequently occur in high impact sports such as North American football. The long term effects of concussive events on physical and psychological wellbeing are the focus of ongoing research. The purpose of this study was to determine if concussive events increase the incidence of depression in active semi-professional and professional North American football players.MethodsAn anonymous online survey was sent to 200 players to collect the following self-reported data: position played, years played, number of concussions sustained and subsequent depressive symptoms using the Center for Epidemiologic Studies Depression (CESD-R) scale. An independent T-test was used to determine differences in the number of concussive events in those with CESD-R scores <16 vs. ≥16, where scores ≥16 are indicative of a depressed state. Likewise, an independent T-test was used to compare CESD-R scores between players with ≥3 concussions vs. ≤2.ResultsIndividuals with a CESD-R score ≥16, sustained a significantly greater number of concussions (3.8 vs. 1.6) than those who scored <16 (p < 0.001). Further analysis also revealed significantly higher CESD-R scores in players who had sustained ≥3 concussions (24.0 vs. 15.6) than those with ≤2 (p < 0.05).ConclusionWithin the parameters of this study, players that were classified as depressed had sustained significantly more concussions compared to those who were not classified as depressed. Further, multiple concussive events (≥3) appears to increase symptoms of depression.