Vascular and Metabolic Consequences of Adopting a Westernized Lifestyle

Study Overview
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Brief Summary
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The purpose of this study is to determine if short-term adoption of a Westernized lifestyle characterized by physical inactivity and increased consumption of fructose will result in metabolic and vascular dysfunction. Healthy individuals aged 18-45 years old will undergo an acute period of physical inactivity (10 days) coupled with increased fructose consumption. Augmented fructose consumption will be achieved via commercially available soda beverages which are high in fructose. Vascular and metabolic function measures will be performed before and after the 10-day intervention.

Detailed Description
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Men and women who regularly engage in >10,000 steps per day, age 18-45 years, body mass index < 30 kg/m2, and with no history of chronic disease will be recruited. Subjects who are eligible will undergo an acute period of physical inactivity (10 days) coupled with increased fructose consumption (6 cans/day). Physical activity levels will be assessed via a pedometer to quantify if individuals achieve <5000 steps/day. Vascular and metabolic function measures will be performed before and after the 10-day intervention.

Official Title
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Vascular and Metabolic Consequences of Adopting a Westernized Lifestyle

Conditions
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Vascular Diseases

Intervention / Treatment
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* Other: Fructose and physical inactivity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women who regularly engage in >10,000 steps per day Age 18-45 years Body mass index < 30 kg/m2 No history of chronic disease Exclusion Criteria: Known cardiovascular disease including hypertension, heart failure, coronary artery disease, and stroke Renal or hepatic diseases Active cancer Autoimmune diseases Current use of immunosuppressant therapy Excessive alcohol consumption (> 14 drinks/week for men and >7 drinks/week for women) Current tobacco use Current pregnancy Diagnosis of type 2 diabetes Regular consumption of >2 non-diet sodas/day

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Fructose and physical inactivity<br>Subjects will consume 6 cans of soda per day and restrict their physical activity. | Other: Fructose and physical inactivity<br>* Subjects will drink 6 cans of regular sodas daily (divided throughout the day) and will decreased physical activity to less than 5000 steps daily for 10 days.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Insulin-stimulated leg blood flow | Subjects will be instrumented with EKG for contrast-enhanced ultrasound (CEU) measurements. We will perform a hyperinsulinemic euglycemic clamp to evaluate microvascular perfusion of skeletal muscle via CEU. Insulin will be infused at a constant rate to mimic postprandial insulin concentrations and glucose maintained at fasting values via a variable 20% dextrose infusion. At baseline and in the steady state phase of the insulin clamp, we will assess microvascular perfusion in the vastus lateralis muscle using CEU (IE-33, Philips Ultrasound), via infusion of perflutren lipid microspheres. Microvascular perfusion will be assessed as an A-value. A is the video intensity plateau after complete replenishment reflecting relative microvascular blood volume (MBV). | this will be assessed at baseline and at the final visit (10 days) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Brachial artery flow mediated dilation (FMD) | Brachial artery FMD will be assessed at baseline and at 10 days. FMD is a measurement of conduit artery endothelial function. FMD is assessed immediately after each PWV measurement. Shear rate AUC until peak diameter is calculated as stimulus for FMD and used in covariate analysis. All measurements will be performed by the same technician. | this will be assessed at baseline and at the final visit (10 days) | 
| Change in carotid femoral pulse wave velocity (cfPWV) | It is the gold standard non-invasive index of arterial stiffness. Transit time between carotid and femoral pressure waves is calculated using the foot-to-foot method. cfPWV is calculated as distance traveled by the pulse wave (i.e., femoral location-sternal notch minus sternal notch-carotid location) divided by pulse transit time. All the measurements will be done by the same technician | this will be assessed at baseline and at the final visit (10 days) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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arterial stiffness, endothelial dysfunction, fructose, physical inactivity