Acute Effects of E-Cigarette Aerosol Inhalation

Study Overview
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Brief Summary
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The purpose of this study is to examine the acute effects of nicotine free electronic cigarette aerosol on vascular function in healthy, non-smokers. This study comprises a portion of a larger study comparing results of vascular function in nonsmokers to vascular function in healthy smokers chronically exposed to nicotinized electronic cigarette aerosol versus conventional cigarettes.

Detailed Description
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The purpose of this study is 1) to examine the acute effects of nicotine free e-cigarette aerosol on vascular function in healthy, non-smokers and 2) to examine and compare vascular function in healthy smokers chronically exposed, at baseline and after 12 months, to nicotinized e-cigarette aerosol versus conventional cigarettes as compared to age, gender and body mass index-matched nonsmokers. Vascular function (microvascular reactivity via dynamic femoral oximetry, arterial hyperemia, femoral artery flow-mediated dilation, central pulse-wave velocity, neurovascular reactivity) will be assessed as part of a single integrated MRI protocol. The outcome of the project will provide new insight into the acute and chronic effects of e-cigarette aerosol inhalation in terms of surrogate markers of endothelial dysfunction (EDF), the prime promoter of atherosclerotic cardiovascular disease, and aid toward establishment of future public health advisories.

Official Title
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Acute and Long-term Effects of E-Cigarette Aerosol Inhalation on Biomarkers of Endothelial Function and Vascular Reactivity

Conditions
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Endothelial Dysfunction, Biochemical Markers

Intervention / Treatment
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* Drug: Electronic Cigarette Aerosol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • BMI of 18.5 - 30 Exclusion Criteria: Cancer HIV Mental illness Overt cardio- or neurovascular disease (prior heart attack, stroke, transient ischemic attacks) Serious arrhythmias Bronchospastic disease Upper respiratory tract infection within the past six weeks Chronic medication or antibiotics Claustrophobia / contraindications for MRI

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Healthy, Non-Smokers<br>Non-nicotinized electronic cigarette aerosol (16 2-second long puffs) | Drug: Electronic Cigarette Aerosol<br>* 16 two-second-long puffs from a non-nicotinized electronic cigarette.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in serum protein levels (micrograms) of inflammatory biomarkers (HMGB-1, RAGE, ICAM, CRP) in non-smoking healthy subjects before and after electronic cigarette aerosol inhalation. | High mobility group box-1 (HMGB1), receptor for advanced glycation end products (RAGE), intercellular adhesion molecule (ICAM1) and C-reactive protein (CRP) will be monitored in serum from subjects by ELISA assays measuring the exact concentration of moieties based on absorbance values emanating from the serum samples. Using standard curves, the amount of these biomarkers will be monitored in the range of nmole or pmole/microgram of serum protein. Measurements will be carried out in triplicate for each sample. Data will be quantified as amount of biomarker/microgram serum protein. | Baseline to six hours | 
| Aortic pulse-wave velocity (meters/second) | Stiffness of aorta | Baseline to six Hours | 
| Femoral artery flow-mediated dilation (% fractional change in cross-sectional area) | Degree of dilation of femoral artery during hyperemia (the transient increase in blood flow velocity) | Baseline to six Hours | 
| Washout time (seconds) | Transit time of desaturated capillary blood from tissue to the imaging location | Baseline to six Hours | 
| Upslope (%HbO2/seconds) | Tissue oxygen resaturation rate | Baseline to six Hours | 
| Overshoot (%HbO2) | Degree of overcompensatory effect in supply of oxygen after ischemia | Baseline to six Hours | 
| Breath hold index (meters/seconds^2) | Rate of increase in blood flow velocity in the superior sagittal sinus from intermittent volitional apnea | Baseline to six Hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Inflammation