Chronic Cardiovascular and Gut-bacteria Effects of Phenolic Rich Oats in Adults With Above Average Blood Pressure

Not Applicable

• Conditions: Healthy
• Interventions: Other: Control; Other: High avenanthramide, phenolic acid; Other: Low avenanthramide, medium phenolic acid

• Registration Number: NCT02847312
• Lead Sponsor: University of Reading

Brief Summary

In this proposed human trial, the investigators aim to establish whether 4 weeks of daily consumption of beta-glucan matched meals providing either a high dose or a moderate dose of oat avenanthramides and phenolic acids leads to dose-dependent chronic improvements in markers of CVD risk and gut health relative to an energy matched control intervention in healthy adults with above average blood pressure.

Detailed Description

* To investigate the chronic effects of daily intake of oat products on flow mediated dilatation of the brachial artery (FMD; primary endpoint), microvascular endothelial function (measured by laser Doppler iontophoresis), pulse wave analysis, gut microbiota diversity, 24h blood pressure, activity of the renin angiotensin system, markers related to cellular production of nitric oxide and reactive oxygen species, inflammatory cytokines, and further potentially emerging biochemical markers of CVD risk.

* To establish if phenolic acids and avenanthramides from oat products exert cardiovascular and microbial effects in a dose dependent manner.

* To measure urinary and fecal excretion of avenanthramide and phenolic acid metabolites.

To explore correlations between bacterial population changes and CVD risk markers.

Study Timeline

• Status Verified: 2016-07
• Study Start: 2016-07
• Study First Submitted: 2016-07-25
• Study First Submitted QC: 2016-07-27
• Last Update Submitted: 2016-07-27
• Study First Posted: 2016-07-28
• Last Update Posted: 2016-07-28
• Primary Completion: 2017-04
• Study Completion: 2017-04

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Above average blood pressure (i.e. systolic 120-159 mmHg and diastolic 75-99 mmHg)

Exclusion Criteria

• Abnormal biochemical, haematological results as assessed at health screening
• Hypertension (i.e. SBP/DBP ≥160/100 mm Hg)
• BMI >35
• Current smoker or ex-smoker ceasing <3 months ago
• Past or existing medical history of vascular disease, diabetes, hepatic, renal, haematological, neurological, thyroidal disease or cancer
• Prescribed or taking lipid lowering, antihypertensive, vasoactive (e.g. Viagra), anti-inflammatory, antibiotic or antidepressant medication
• Allergies to whole grains
• Parallel participation in another research project
• Having flu vaccination or antibiotics within 3 months of trial start
• Chronic constipation, diarrhea or other chronic gastrointestinal complaint
• On a weight reduction regime or taking food, probiotics or prebiotics supplements or laxative within 3 months of trial start
• Performing high level of physical activity (i.e. ≥150min aerobic exercise/week)
• Consumption of ≥21 units of alcohol/week
• Females who are breast-feeding, may be pregnant, lactating or, if of reproductive age and not using a reliable form of contraception (including abstinence)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Control	Control	69.8g Cream of Rice + 8.1g Cellulose + 4.8g Pectin + 60g Melba Toast
High avenanthramide, phenolic acid	High avenanthramide, phenolic acid	66.8g Pepsico Oatmeal + 60g Oat cake
Low avenanthramide, medium phenolic acid	Low avenanthramide, medium phenolic acid	17g Oatwell + 63.6g Cream of Rice + 60g Melba Toast

Primary Outcome Measures

Name	Time	Method
Flow mediated dilatation	20 weeks	Technique to assess the flexibility of teh endothelium in larger peripheral blood vessels, magnitude of increase in percentage from baseline to after 4 weeks treatment.

Secondary Outcome Measures

Name	Time	Method
Plasma nitric oxide analysis	22 weeks	Concentration of nitric oxide in nmol from Baseline to 4weeks treatment
Renin activity	22 weeks	Renin activity in ng/(mL\*hour)
Urine and plasma metabolomic footprint using NMR	22 weeks
Gut microbiota changes	22 weeks	Gut microbiota diversity and relative abduance change from Baseline to 4weeks treatment
NADPH oxidase activity in neutrophil blood cells	22 weeks	NADPH oxidase activity will be calculated as the difference between values obtained in PMA from Baseline to 4weeks treatment
Inflammatory markers	22 weeks	Inflammatory marker levels change from Baseline to 4weeks treatment
Laser Doppler Iontophoresis	20 weeks	Magnitude of increase from Baseline to 4weeks treatment
Plasma microparticles	22 weeks	Microparticles in counts/uL

Trial Locations

Locations (1)

Hugh Sinclair Unit of Human Nutrition; 🇬🇧 Reading, United Kingdom