The effect of microencapsulated watermelon rind (Citrullus lanatus) and beetroot (Beta vulgaris L.) ingestion on ischemia/reperfusion-induced endothelial dysfunction: a randomised clinical trial.

Endothelial dysfunction is commonly associated with a cardiovascular event, such as myocardial infarction. Myocardial infarction is marked by an ischemia/reperfusion (IR) phenomenon associated with endothelial dysfunction, contributing even more to future cardiovascular events. Although the supplementation with L-citrulline and nitrate from watermelon and beetroot have been used to improve vascular function, the effect of microencapsulated watermelon rind (WR) or its co-ingestion with beetroot (WR + B) on endothelial IR injury has not been addressed. Therefore, this study aimed to investigate the effect of a single dose of WR and WR + B on IR-induced macro-and microvascular dysfunction. In a randomized, crossover, placebo-controlled study, 12 volunteers underwent macro (flow-mediated dilation) and microvascular (muscle oxygen saturation) assessment and blood collection (to measure L-citrulline, L-arginine, nitrate and nitrite) before and after 20 min of blood occlusion in WR, WR + B and placebo conditions. Prolonged ischemia induced endothelial dysfunction in the macro but not in the microvasculature. The WR and WR + B supplementation significantly restored FMD after IR injury compared to the placebo (p < 0.05). However, there was no significant difference between WR and WR + B in the macrovascular function (p > 0.05). Plasma L-citrulline, L-arginine, nitrate, and nitrite significantly increased (p > 0.05) after WR and WR + B supplementation compared to the placebo. A single dose of WR and WR + B effectively minimizes IR-induced macrovascular endothelial dysfunction in healthy individuals. Beetroot co-ingestion with watermelon did not provide an additional effect of endothelial dysfunction induced by IR (NCT04781595, March 4, 2021).

A single dose of microencapsulated cocoa supplementation attenuated eccentric exercise-induced endothelial dysfunction.

In the present study, it was evaluated whether microencapsulated cocoa supplementation could attenuate endothelial dysfunction caused by eccentric exercise in healthy subjects. Thirteen volunteers were enrolled in this double-blind, placebo-controlled, crossover study. Flow-mediated dilatation (FMD), blood flow and muscle O2 saturation (StO2) were evaluated by ultrasound and near-infrared spectroscopy (NIRS), respectively, before and after microencapsulated cocoa supplementation. The eccentric exercise was performed after microencapsulated cocoa supplementation to generate vascular dysfunction. Eccentric exercise significantly reduced FMD in the PLA condition, but cocoa attenuated this exercise effect. No significant effect was observed on muscle StO2 and blood flow after eccentric exercise and nutritional supplementation. In conclusion, the present study showed that a single dose of microencapsulated cocoa ingestion attenuated FMD-induced eccentric exercise. These findings suggest that a single dose of microencapsulated cocoa may be an alternative nutritional strategy to attenuate vascular dysfunction induced by eccentric exercise in healthy individuals.

Current Evidence of Watermelon (Citrullus lanatus) Ingestion on Vascular Health: A Food Science and Technology Perspective.

The amino acid L-arginine is crucial for nitric oxide (NO) synthesis, an important molecule regulating vascular tone. Considering that vascular dysfunction precedes cardiovascular disease, supplementation with precursors of NO synthesis (e.g., L-arginine) is warranted. However, supplementation of L-citrulline is recommended instead of L-arginine since most L-arginine is catabolized during its course to the endothelium. Given that L-citrulline, found mainly in watermelon, can be converted to L-arginine, watermelon supplementation seems to be effective in increasing plasma L-arginine and improving vascular function. Nonetheless, there are divergent findings when investigating the effect of watermelon supplementation on vascular function, which may be explained by the L-citrulline dose in watermelon products. In some instances, offering a sufficient amount of L-citrulline can be impaired by the greater volume (>700 mL) of watermelon needed to reach a proper dose of L-citrulline. Thus, food technology can be applied to reduce the watermelon volume and make supplementation more convenient. Therefore, this narrative review aims to discuss the current evidence showing the effects of watermelon ingestion on vascular health parameters, exploring the critical relevance of food technology for acceptable L-citrulline content in these products. Watermelon-derived L-citrulline appears as a supplementation that can improve vascular function, including arterial stiffness and blood pressure. Applying food technologies to concentrate bioactive compounds in a reduced volume is warranted so that its ingestion can be more convenient, improving the adherence of those who want to ingest watermelon products daily.

Improved microvascular reactivity after aged garlic extract intake is not mediated by hydrogen sulfide in older adults at risk for cardiovascular disease: a randomized clinical trial.

PURPOSE: This study aimed to investigate the effects of AGE on microvascular reactivity, systolic blood pressure (SBP), and diastolic blood pressure (DBP) in older individuals at high risk for cardiovascular disease (CVD). Urinary thiosulfate was also investigated as an indirect marker of endogenous hydrogen sulfide (H2S) synthesis. The study was conducted in a randomized, double-blind, crossover, and placebo-controlled way. METHODS: Twenty-eight participants (14 male), 67 ± 6 years old with CVD risk factors, ingested 2.4 g of AGE or placebo (PLA). Near-infrared spectroscopy evaluated tissue oxygen saturation (StO2) during a vascular occlusion test (30 s baseline, 5 min occlusion, and 2 min reperfusion). The upslope of StO2 signal after cuff release was calculated to measure microvascular reactivity. Urinary thiosulfate levels were measured using a high-performance liquid chromatography system. RESULTS: The upslope of StO2 was significantly faster after AGE (1.01 ± 0.37% s-1) intake compared to PLA (0.83 ± 0.35% s-1; P < 0.001; d = 0.50). Relative changes in Δ% SBP from pre- to post-AGE intake (- 5.17 ± 5.77%) was significantly different compared to Δ% PLA (0.32 ± 5.99%; P = 0.001; d = 0.93). No significant changes in urinary thiosulfate concentrations were observed between interventions. Moreover, no significant gender effect in any parameter assessed was found. CONCLUSION: This study demonstrated that a single dose of AGE improved microvascular reactivity in older adults at risk of CVD despite such an effect was not linked with urinary thiosulfate levels. This trial was registered at clinicaltrials.gov as NCT04008693 (May 19, 2020).

Turmeric root extract supplementation improves pre-frontal cortex oxygenation and blood volume in older males and females: a randomised cross-over, placebo-controlled study.

Ageing is associated with endothelial dysfunction and reduced cerebral blood flow and oxygenation. The present study aimed to investigate whether turmeric supplementation could improve cerebral oxygenation and blood volume during brain activation via dynamic handgrip exercise in older males and females. Twelve older males and females were studied using a double-blind, placebo-controlled, cross-over design. Participants ingested turmeric root extract or placebo. Heart rate and blood pressure were measured before and 2 hours after supplementation. Afterward, the exercise protocol was started, and cerebral oxygenation and blood volume were evaluated. During exercise, changes in cerebral oxygenation were higher after turmeric extract supplementation, as was blood volume compared to placebo. Changes in heart rate, systolic blood pressure, and diastolic blood pressure were not significant. The current findings indicate the potential for curcumin as an intervention for improving cerebral oxygenation and blood volume changes in older males and females. Clinical trial registry: NCT04119752.

Dietary nitrate improves skeletal muscle microvascular oxygenation in HIV-infected patients receiving highly active antiretroviral therapy: a randomised, double-blind, cross-over, placebo-controlled study.

HIV-1 proteins and highly active antiretroviral therapy (HAART) have been associated with microvascular endothelial dysfunction. Although nitrate-rich beetroot juice (NR-BJ) consumption has been shown to improve endothelial function in clinical population, its effects in HIV-infected patients has not been addressed. We investigated the effect of a single dose of NR-BJ on muscle oxygen saturation parameters in response to a handgrip exercise in HIV-infected patients. Fifteen HIV-infected patients received NR-BJ or nitrate-depleted beetroot juice (ND-BJ) in a double-blind cross-over design. Near-IR spectroscopy was utilised to assess muscle oxygen saturation parameters during rhythmic handgrip exercise after NR-BJ or ND-BJ supplementation. A significant faster muscle oxygen desaturation rate during exercise (-7·97 (sd 5·00) v. -5·45 (3·94) %/s, P = 0·005) and muscle oxygen resaturation rate during exercise recovery (0·43 (0·24) v. 0·28 (0·24) %/s, P = 0·030) after NR-BJ ingestion was found. However, no significant difference in exercise time until fatigue was observed. Salivary nitrite and urinary nitrate concentration were analysed after NR-BJ or ND-BJ. A significant increase in salivary nitrite and urinary nitrate in NR-BJ was observed compared with ND-BJ (P < 0·05). Our findings suggest that NR-BJ consumption may acutely improve muscle oxygen saturation during exercise and exercise recovery in HIV-infected patients undergoing HAART and who are expected to present microvascular damage. Thus, future studies investigating the chronic effects of NR-BJ are warranted to delineate a better nutritional strategy based on nitrate-rich foods.

Effects of fish protein hydrolysate ingestion on postexercise aminoacidemia compared with whey protein hydrolysate in young individuals.

The aminoacidemia resulting from food protein digestion in response to exercise plays an underlying role in the rate of muscle protein synthesis. Whey protein hydrolysate (WPH) has been demonstrated to cause more pronounced postexercise aminoacidemia compared with casein and soy. Although fish protein has been demonstrated to be a great source of amino acids, there is no data available providing information about the postexercise aminoacidemia after fish protein hydrolysate (FPH) intake. The present study investigated the characteristic patterns of postexercise aminoacidemia after WPH and FPH intake in nine physically active subjects (six males and three females). In a crossover, double-blind, and randomized design, all participants received oral doses of either 0.25 g/kg of FPH or WPH or placebo (PLA) immediately after a resistance exercise bout. Blood samples were taken before and at 30, 60, 90, 120 and 180 min after supplementation. There was a significant increase in plasma total amino acids (TAA), essential amino acids (EAA), branched-chain amino acids (BCAA), and leucine concentrations at 30 and 60 min after FPH supplementation, and at 30, 60, 90, and 120 min after WPH as compared to PLA. No significant differences were observed in plasma TAA, EAA, BCAA, and leucine concentrations between FPH and WPH at any time point, and there were no significant difference observed in the area under the curve for TAA, EAA, BCAA, and leucine between FPH and WPH. In conclusion, both FPH and WPH showed a rapid and pronounced postexercise aminoacidemia. FPH presented itself to be an alternative food source of rapidly digested proteins to be used after resistance exercise. PRACTICAL APPLICATION: Fish protein hydrolysate (FPH) demonstrated a rapid and pronounced postexercise aminoacidemia. Whey protein hydrolysate showed similar effects. FPH is presented as an alternative food source of rapidly digested proteins to be consumed by the population, especially physically active individuals.

A single dose of beetroot juice improves endothelial function but not tissue oxygenation in pregnant women: a randomised clinical trial.

Beetroot juice (BJ) consumption has been associated with improved cardiovascular health owing to an increase in NO bioconversion. This study evaluates the effect of BJ consumption on macrovascular endothelial function (flow-mediated dilation (FMD)) and muscle oxygen saturation (StO2) parameters in pregnant women within a randomised, crossover, double-blind design in which twelve pregnant women consumed a single dose (140 ml) of BJ or placebo (PLA). Urinary nitrate was assessed before (T0) and 150 min after BJ/PLA consumption. FMD was used to evaluate macrovascular endothelial function, and near-IR spectroscopy was used to evaluate muscle StO2 parameters during the occlusion and reperfusion phases, which were taken at baseline (PRE) and 120 and 140 min after BJ/PLA consumption, respectively. A significant increase in urinary nitrate was observed at 150 min after BJ consumption when compared with T0 (BJ: 0·20 (sd 0·13) v. T0: 0·02 (sd 0·00), P=0·000) and PLA intervention (PLA: 0·02 (sd 0·00), P=0·001). FMD improved after BJ consumption when compared with PRE (BJ: 11·00 (sd 1·67) v. PRE: 5·53 (sd 1·17), P=0·000) and PLA (5·34 (sd 1·31), P=0·000). No significant difference between PLA and PRE in FMD (P=1·000) was observed. In StO2 parameters, a difference was not observed after BJ consumption compared with PRE and PLA intervention. The data demonstrate that a single dose of 140 ml of BJ consumption improves macrovascular endothelial function, but not StO2 parameters.

Beetroot-based gel supplementation improves handgrip strength and forearm muscle O2 saturation but not exercise tolerance and blood volume in jiu-jitsu athletes.

The ergogenic effect of beetroot on the exercise performance of trained cyclists, runners, kayakers, and swimmers has been demonstrated. However, whether or not beetroot supplementation presents a beneficial effect on the exercise performance of jiu-jitsu athletes remains inconclusive. Therefore, the present study assessed the effect of beetroot-based gel (BG) supplementation on maximal voluntary contraction (MVC), exercise time until fatigue (ETF), muscle O2 saturation (SmO2), blood volume (tHb), and plasma nitrate and lactate in response to handgrip isotonic exercise (HIE) in jiu-jitsu athletes. In a randomized, crossover, double-blind design, 12 jiu-jitsu athletes performed 3 sets of HIE at 40% of the MVC until fatigue after 8 days (the eighth dose was offered 120 min previous exercise) of BG supplementation or a nitrate-depleted gel (PLA), and forearm SmO2 and tHb were continuously monitored by using near-infrared spectroscopy. Blood samples were taken before, immediately after exercise, and 20 min after exercise recovery in the PLA and BG conditions. MVC was evaluated at baseline and 20 min after HIE. There was a significant reduction in ΔMVC decline after HIE in the BG condition. Forearm SmO2 during exercise recovery was significantly greater only after BG supplementation. No significant difference in ETF and tHb were observed between both BG and PLA in response to HIE. Plasma nitrate increased only after BG, whereas the exercise-induced increase in plasma lactate was significantly lower in BG when compared with PLA. In conclusion, BG supplementation may be a good nutritional strategy to improve forearm SmO2 and prevent force decline in response to exercise in jiu-jitsu athletes.