Absorption and Metabolism of Olive Leaf Extract and Its Effect on Vascular Reactivity and Cytokine Concentrations

Not Applicable

Completed

• Conditions: Absorption and Metabolism; Effect on Vascular Function; Effect on Cytokine Concentrations
• Interventions: Dietary Supplement: Olive leaf extract capsules

• Registration Number: NCT01479699
• Lead Sponsor: University of Reading

Brief Summary

The purpose of this study is to determine how olive leaf is absorbed and metabolised and also whether it has any effect on the elasticity of blood vessels and the immune system.

Detailed Description

The purpose of this study is to determine how olive leaf is absorbed and metabolised and also whether it has any effect on vascular function and cytokine concentrations.

Study Timeline

• Study Start: 2011-06
• Primary Completion: 2011-10
• Study Completion: 2011-10
• Status Verified: 2011-11
• Study First Submitted: 2011-11-22
• Study First Submitted QC: 2011-11-22
• Last Update Submitted: 2011-11-22
• Study First Posted: 2011-11-24
• Last Update Posted: 2011-11-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 18

Inclusion Criteria

• 19-40 years, non-smokers, able to swallow capsules, have a Body Mass Index (BMI) of 18.5-30, have a normal liver function and haematology and a max alcohol intake of <21 units/week

Exclusion Criteria

• Those who suffer from any form of disease, including endocrine disease, liver disease, diabetes mellitus, myocardial infarction, blood clotting disorder, reproductive disorder, gastrointestinal disease or a chronic gastrointestinal disorder.
• Individuals who are vegetarian, have dietary restrictions or on a weight reducing diet will not be recruited.
• Subjects who have been taking antibiotics in previous 3 months before study will not be included in the study
• Females who may be pregnant, or if of childbearing potential and are not using effective contraceptive precautions will be excluded.
• Blood pressure > 150/90 mmHg
• Haemoglobin < 125 g/l for male, < 110 g/l for female
• Gamma GT (liver enzymes) > 80 IU/l
• Cholesterol > 6.5 mmol/l
• Had suffered a myocardial infarction or stroke in the previous 12 months
• On any lipid-modifying medication
• On any medication affecting blood clotting
• Individuals taking vitamin and/or fish oil supplements

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Placebo capsule	Olive leaf extract capsules	Four placebo capsules containing safflower oil only
Olive leaf extract capsule	Olive leaf extract capsules	Four olive leaf capsules. Each containing 4mg oleuropein plus safflower oil.

Primary Outcome Measures

Name	Time	Method
Absorption and metabolism	0. 0.5, 1, 1.5, 2, 3, 4, 6, 8 hours post ingestion (blood) 0, 0-4, 4-8 and 8-24 hours post ingestion (urine)	Olive leaf polyphenol metabolites measured in blood and urine samples

Secondary Outcome Measures

Name	Time	Method
Vascular function	0, 2, 4, 6 hours post ingestion (LDI) 0, 0.5, 1, 1.5, 2, 3, 4, 6 and 8 hours post ingestion (DVP)	Vascular function was assessed via two methods: Laser Doppler Iontophoresis (LDI) and Digital Volume Pulse (DVP)
Cytokine concentration	0, 1, 3 and 6 hours post ingestion	Concentrations of IL-8, IL-1beta, IL-6, IL-10 and TNF-alpha will be measured in whole blood stimulated with LPS.

Trial Locations

Locations (1)

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