Evaluation of the Effect of Spirulina-Silicon Supplementation on the Morphological, Biomechanical and Functional Characteristics of the Arterial Wall in the Elderly

Study Overview
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Brief Summary
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The investigators hypothesize that spirulina-silicon supplementation will lead to an improvement in vasomotor endothelial function, followed by decreased arterial wave velocity on the aorta and central arterial pressure compared to placebo subjects.

Official Title
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Evaluation of the Effect of Spirulina-Silicon Supplementation on the Morphological, Biomechanical and Functional Characteristics of the Arterial Wall in the Elderly

Conditions
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Elderly

Intervention / Treatment
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* Dietary Supplement: 3.5g of spirulina per day in 1% silicone
* Dietary Supplement: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The subject must have given their free and informed consent and signed the consent form The subject must be a member or beneficiary of a health insurance plan The subject is available for 6 months of follow-up The subject must not have any pre-existing chronic illness nor any revealed during the pre-inclusion visit, either treated or requiring treatment according to current recommendations Exclusion Criteria: The subject is participating in an interventional study, or is in a period of exclusion determined by a previous study The subject refuses to sign the consent It is impossible to give the subject informed information The patient is under safeguard of justice or state guardianship Presence of a chronic cardio-vascular and/or metabolic illness, known or revealed by the pre-inclusion exam and requiring treatment in accordance to official recommendations (HAS) Any other chronic pathology requiring medical treatment History of uric acid metabolism disorders (hyperuricemia, gout, urolithiasis). Subject presenting a loss of limitation of autonomy Treated with hormone replacement therapy in females Active smoker or drug user Presence of an abnormality revealed by the pre-inclusion biological assessment of dyslipidemia justifying a prescription medication, diabetes or intolerance to glucose (insulin resistance). Presence of a stenosis (greater than 50% in diameter, NASCET method) or carotid occlusion revealed by the echo-Doppler screening test. Presence of an aneurysm (dilation> 30 mm) of the abdominal aorta revealed by the echo-Doppler screening test. Arteriopathy of the lower limbs (toe systolic pressure (tsp) <0.7) revealed by the screening test (SysToe™ device). Subject already taking a food supplement based on spirulina or silicon. History of cardio-vascular disease or heart attack Subject develops a chronic illness requiring medical treatment for more than 7 days or a surgical intervention leading to incapacity for more than 7 days,or a pathological event during the 14-day period before each follow-up visit, or a serious adverse event

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br> | Dietary Supplement: placebo<br>* 5 tablets per day of potato-based placebo<br>|
| Experimental: Spirulina-Silicon supplementation<br> | Dietary Supplement: 3.5g of spirulina per day in 1% silicone<br>* 5 tablets of 700mg per day<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Pressure Waveforms between groups | Applanation tonometry; m.s-1 | Month 6 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Pressure Waveforms between groups | Applanation tonometry; mm | Day 0 | 
| Arterial Pressure Waveforms between groups | Applanation tonometry; mm | Month 1 | 
| Arterial Pressure Waveforms between groups | Applanation tonometry; mm | Month 3 | 
| Vasomotor endothelial function between groups | % post-ischemic vasorelaxation | Day 0 | 
| Vasomotor endothelial function between groups | % post-ischemic vasorelaxation | Month 1 | 
| Vasomotor endothelial function between groups | % post-ischemic vasorelaxation | Month 3 | 
| Vasomotor endothelial function between groups | % post-ischemic vasorelaxation | Month 6 | 
| intima-media thickness of common carotid arteries | echography; mm | Day 0 | 
| intima-media thickness of common carotid arteries | echography; mm | Month 6 | 
| left ventricular diastolic function | kPa | Day 0 | 
| left ventricular diastolic function | kPa | Month 6 | 
| Central venous pressure | mmHg | Day 0 | 
| Central venous pressure | mmHg | Month 1 | 
| Central venous pressure | mmHg | Month 3 | 
| Central venous pressure | mmHg | Month 6 | 
| Arterial Pressure Waveforms of females compared to males | Applanation tonometry; m.s-1 | Month 6 | 
| Vasomotor endothelial function of females compared to males | % post-ischemic vasorelaxation | Month 6 | 
| Bone density | dual-photon absorptiometry | Day 0 | 
| Bone density | dual-photon absorptiometry | Month 6 | 
| Biological markers of vascular remodeling, oxidative stress and inflammation | Total cholesterol, High density lipoproteins, Triglycerides, Complete Blood Count, high-sensitivity C-reactive protein, toe systolic pressure, Oxidized low density lipoprotein, Vitamin E, Vitamin C, Reduced (GSH) and Oxidized (GSSG) Glutathione ratio, Procollagen type I N propeptide, cross-linking telopeptide of type I collagen, Elastin, Osteoprotegerin, Sclerotin, Calcium, Phosphorus, Alkaline Bone Phosphatase | Day 0 | 
| Biological markers of vascular remodeling, oxidative stress and inflammation | Total cholesterol, High density lipoproteins, Triglycerides, Complete Blood Count, high-sensitivity C-reactive protein, IsoP, Oxidized low density lipoprotein, Vitamin E, Vitamin C, Reduced (GSH) and Oxidized (GSSG) Glutathione ratio, Procollagen type I N propeptide, cross-linking telopeptide of type I collagen, Elastin, Osteoprotegerin, Sclerotin, Calcium, Phosphorus, Alkaline Bone Phosphatase | Month 6 |