The objective of the study is to investigate the effects of beetroot juice, a high nitrate-containing vegetable, on postprandial vascular activity after a high-fat load in overweight and slightly obese male subjects.
ID
Source
Brief title
Condition
- Lipid metabolism disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The primary parameter is the capacity of vessels to respond to a standardized
high-fat meal during the postprandial period as assessed with flow-mediated
dilation (FMD) of the brachial artery.
Secondary outcome
Secondary study endpoints are the responsiveness of larger arteries to
postprandial lipemia measured by pulse wave analysis (PWA) and pulse wave
velocity (PWV). Microcirculatory effects will be visualized by retinal imaging.
In plasma, metabolic risk markers related to the metabolic syndrome will be
investigated: postprandial concentrations of factors related to low-grade
inflammation and endothelial activation, and postprandial lipid and glucose
metabolism. Finally, effects on blood pressure and heart rate will be studied.
Background summary
Increased postprandial lipemia may increase the risk for cardiovascular
diseases. An important mechanistic link between lipemia following a high-fat
meal and adverse cardiovascular events is lipid-mediated endothelial
activation. Therefore, it is important to identify nutrients that can
neutralize this acute vascular disturbance. We hypothesize that beetroot juice,
a food rich in inorganic nitrate, could improve vascular activity during the
postprandial phase.
Study objective
The objective of the study is to investigate the effects of beetroot juice, a
high nitrate-containing vegetable, on postprandial vascular activity after a
high-fat load in overweight and slightly obese male subjects.
Study design
Using a randomized crossover design, subjects will receive in random order two
different interventions with a washout period of at least 7 days. During each
test, the postprandial response is measured.
Intervention
Subjects will receive beetroot juice or an isocaloric carbohydrate drink as
control on two separate occasions. The drinks will be provided with two muffins
providing 56.6 g fat.
Study burden and risks
Before the start of the study subjects will be screened to determine
eligibility during two visits of respectively 15 and 10 minutes. During these
visits, body weight, height, waist circumference and blood pressure will be
measured and a venous blood sample (3.5mL) will be drawn. Following screening,
subjects will be asked to attend the research facilities at Maastricht
University, on two separate occasions. During these visits, an intravenous
cannula will be inserted in an antecubital vein. Before and after meal
consumption, nine blood samples (79.5 mL each day) will be drawn over the next
four hours. In total, 166 mL of blood will be sampled (2 x 3.5 mL during
screening and 2 x 79.5 mL during the study). During the day, two retinal
photographs will be taken. Vascular activity and function measurements, i.e.
FMD, PWA and PWV, are performed before and after meal consumption. Total time
investment for the subjects will be approximately 745 minutes. During this
period, subjects will remain at the university. On rare occasions, blood
sampling might cause bruises or haematoma.
Universiteitssingel 50, P.O. Box 616
6229 ER, Maastricht
NL
Universiteitssingel 50, P.O. Box 616
6229 ER, Maastricht
NL
Listed location countries
Age
Inclusion criteria
Healthy overweight and slightly men will be included. Further inclusion criteria are:
- Aged between 18 and 70 years
- Quetelet-index between 28 and 35 kg/m2
- Mean serum triacylglycerol <=1.7 mmol/L
Exclusion criteria
- Women
- Quetelet-index between <28 or >35 kg/m2
- Mean serum triacylglycerol >=1.7 mmol/L
- Indication for treatment with cholesterol-lowering drugs according to the Dutch Cholesterol Consensus
- Current smoker
- Diabetic patients or individuals receiving antidiabetic medication
- Familial hypercholesterolemia
- Abuse of drugs
- More than 21 alcoholic consumptions per week
- Unstable body weight (weight gain or loss >3 kg in the past three months)
- Use of use of medication known to affect serum lipid metabolism
- No severe medical conditions that might interfere with the study.
Severe medical conditions are:
a high blood pressure, epilepsy, asthma, allergies, chronic obstructive pulmonary disease, inflammatory bowel diseases, auto inflammatory diseases and rheumatoid arthritis.
- Active cardiovascular disease like congestive heart failure or recent (<6 months) event (acute myocardial infarction, cerebro vascular accident)
- Use of an investigational product within the previous 1 month
- Not willing to stop the consumption of foods rich in nitrates 3 weeks before the start of the study.
Foods rich in nitrates are:
beets, celery, radishes, turnips and spinach.
- Not willing to give up being a blood donor (or having donated blood) from 8 weeks before the start of the study, during the study and for 4 weeks after completion of the study
- Not or difficult to venipuncture as evidenced during the screening visits
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL39114.068.11 |