Acute and Chronic Effects of Red Beetroot Juice on High-Fat Meal-Induced Endothelial Dysfunction and Cardiometabolic Disturbances
试验速览
- 阶段
- 2 期
- 入组人数
- 15
- 试验地点
- 2
- 主要终点
- Vascular endothelial function
研究概览
简要总结
Aside from aging, numerous factors increase the risk for developing cardiovascular disease (CVD) including diet and nutrition. High-fat meal consumption induces postprandial vascular endothelial dysfunction and other cardiometabolic disturbances (e.g. dyslipidemia and hyperglycemia) in normal weight individuals and is exacerbated in overweight/obese individuals. These postprandial responses are likely largely due to activation of pro-inflammatory and pro-oxidant pathways. Given that much of the day is spent in the postprandial state, this may further impair cardiovascular health in aging overweight/obese individuals. Interventions that attenuate these responses are needed. Red beetroot (Beta vulgaris L.) is an excellent source of bioactive compounds including nitrate, flavonoids, phenolic acids, betalains, carotenoids, and ascorbic acid. These bioactive compounds and their metabolites have been shown to have antioxidative, anti-inflammatory, and cardiovascular-protective effects. These effects, particularly the cardiovascular-protective effects, have been primarily attributed to its high content of nitrate since it is converted to nitric oxide independent of the vascular endothelium via the enterosalivary nitrate-nitrite-nitric oxide pathway. However, red beetroot juice contains a number of other potentially beneficial bioactive compounds and few studies have aimed to determine whether these compounds work independently, additively, or synergistically in exerting these effects. Given the findings of previously conducted research in the broad area of red beetroot juice consumption and human health, it can be suggested that: 1) acute red beetroot juice consumption may prevent or attenuate the adverse postprandial responses to consuming a high-fat meal in individuals with exaggerated responses; and 2) chronic consumption of red beetroot may improve underlying factors contributing to these exaggerated responses. Accordingly, this project aims to: 1) investigate the efficacy of acute and chronic whole red beetroot juice consumption compared with its bioactive components in attenuating postprandial vascular endothelial dysfunction and adverse cardiometabolic responses to a high-fat meal; and 2) to gain insight into the underlying mechanisms responsible.
详细描述
This is a randomized, double-blind, placebo-controlled, 4-period, 4-week crossover pilot clinical trial consisting of 2 postprandial tests for each period. Overweight or obese postmenopausal women and men aged 40 to 65 will be recruited from the greater Fort Collins, CO area. After telephone prescreening, participants will report to the study site for their first visit (Screening) where they will receive verbal and written explanation of the project, provide informed consent, followed by screening assessments. Qualified participants will be scheduled for a baseline visit and randomly assigned to their respective treatments. On the second visit (Baseline) following an overnight fast, anthropometrics and blood pressure will be measured and diet and physical activity records will be collected. Subjects will ingest their respective treatment 10 min prior to consuming the high-fat test meal. Various assessments will be performed and samples collected prior to and up to 4 hours post-meal consumption. At the third visit (Final), all assessments and sample collections will be repeated at the same time points but 24 hours after consuming the last dose of their respective treatments to test chronic rather than acute effects. Subjects will undergo a 4-week washout period before crossing over to the next treatment period. This will be repeated for all 4 treatments.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 40 Years 至 65 Years(Adult, Older Adult)
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Postmenopausal women and men
- •BMI between 25 and 40 kg/m2
排除标准
- •Hypertension, cardiovascular disease, diabetes, cancer, or kidney, liver, or pancreatic disease
- •Individuals taking gastroesophageal reflux, antihypertensive, hypoglycemic, lipid-lowering, hormone replacement, erectile dysfunction medications or nitrates
- •Participating in a weight loss program or actively trying to lose weight
- •Heavy drinkers (> 3 drinks on any given occasion and/or > 7 drinks/week for women, or > 4 drinks on any given occasion and/or > 14 drinks/week for men)
- •Allergy to meals/treatments
- •Consuming > 2 servings red beetroot or beetroot juice/wk
研究组 & 干预措施
70 mL placebo drink
70 mL calorie-matched placebo control drink devoid of nitrate, vitamins, minerals, and polyphenols.
干预措施: 70 mL placebo drink (Dietary Supplement)
70 mL red beetroot juice
70 mL red beetroot juice naturally containing 300 mg nitrate.
干预措施: 70 mL red beetroot juice (Dietary Supplement)
70 mL placebo drink plus potassium nitrate
70 mL calorie-matched placebo control drink containing 489 mg potassium nitrate to deliver 300 mg nitrate.
干预措施: 70 mL placebo drink plus potassium nitrate (Dietary Supplement)
70 mL red beetroot juice without nitrate
70 mL red beetroot juice per day without nitrate.
干预措施: 70 mL red beetroot juice without nitrate (Dietary Supplement)
结局指标
主要结局
Vascular endothelial function
时间窗: 0 and 4 hours post-meal consumption at baseline and 1 month for each treatment period.
Vascular endothelial function will be assessed using reactive hyperemia index (EndoPAT) 0 and 4 hours post-meal consumption.
次要结局
- Blood glucose, insulin, and indices of insulin sensitivity and resistance(0 and 1, 2, and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
- Blood triglycerides(0 and 1, 2, and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
- Blood pressure(0 and 1, 2, and 4 hours post-meal consumption at baseline and 1 month for each treatment period)
- Arterial stiffness(Pre-meal consumption at baseline and 1 month for each treatment period.)
- Heart rate(0 and 1, 2, and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
- Pro-inflammatory biomarkers(0 and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
- Oxidative stress biomarkers(0 and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
- Nitric oxide biomarkers(0 and 1, 2, and 4 hours post-meal consumption at baseline and 1 month for each treatment period.)
研究者
Sarah Johnson
Assistant Professor
Colorado State University
