Does tomato extract improve blood vessel function in healthy people and people with cardiovascular disease?
Atherosclerosis ('furring' of the arteries) affects the functioning of blood vessels, narrowing and eventually blocking them, causing conditions like heart attack and stroke. The Mediterranean diet, which is rich in tomatoes and tomato-based products, has been shown to be associated with a reduced risk of blood vessel damage. In this double blind, placebo-controlled randomised study, the investigators will investigate whether a food supplement containing a standardised extract of tomato improves blood vessel function in both healthy people (aged 40-80), and people with a history of cardiovascular disease. The food supplement is on sale to the public, and the investigators are testing the standard dose. Approximately 72 people will take part at the Clinical Pharmacology Unit at the ACCI Building, Cambridge University Hospitals NHS Trust.
After they have passed screening tests, participants will be allocated by chance to receive either the tomato extract product (Ateronon), or a matching placebo (a dummy capsule with no active ingredients), which they will take once a day for 8 weeks. At the beginning and end of the treatment period, the investigators will test blood vessel stiffness using an ECG machine and external probe. The investigators will also measure forearm blood flow, which involves infusing 3 separate agents that affect how the lining of the blood vessel wall works, and helps to assess whether this is affected by the study treatment. Blood tests will also be used to look at how the food supplement is working and its effects on cholesterol and markers of inflammation. Including the screening period, and a follow-up telephone call two weeks after the end of treatment, participants will be in the study for 14 weeks.
- Placebo Drug
Intervention Desc: Matched placebo capsule, taken once daily for 56 days ARM 1: Kind: Experimental Label: Healthy (placebo) ARM 2: Kind: Experimental Label: Cardiovascular Group (placebo)
- Ateronon Dietary Supplement
Intervention Desc: Tomato extract (lycopene) capsule, taken once daily for 56 days ARM 1: Kind: Experimental Label: Healthy (Ateronon) ARM 2: Kind: Experimental Label: Cardiovascular Group (Ateronon)
- Allocation: Randomized
- Masking: Double Blind (Subject, Investigator)
- Endpoint: Efficacy Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Forearm blood flow ratio (and % change), as measured by venous occlusion plethysmography, in response to intra-arterial acetylcholine infusion.||8 weeks||No|
|Primary||Forearm blood flow ratio and/or absolute flow in the infused arm (and % change), as measured by venous occlusion plethysmography, in response to intra-arterial acetylcholine infusion.||8 weeks||No|
|Secondary||Forearm blood flow ratio and/or absolute flow in the infused arm (& % change), as measured by venous occlusion plethysmography, in response to intra-arterial sodium nitroprusside and L-NMMA infusion.||8 weeks||No|
|Secondary||Evaluation of pulse wave velocity and pulse wave analysis||8 weeks||No|
|Secondary||Pulse wave velocity measured between carotid and femoral artery.||8 weeks||No|
|Secondary||Analysis of Lipoprotein oxidation/circulating markers.||8 weeks||No|
|Secondary||Safety and tolerability parameters, including physical examination, blood pressure, heart rate, 12-lead electrocardiograms (ECGs), clinical laboratory tests and adverse event reporting.||8 weeks||No|