Effects of Sodium Chloride or Its Substitute Salt Potassium Chloride on Vascular Function

Study Overview
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Brief Summary
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This is a prospective, monocentric, randomized trial to investigate how sodium chloride or its substitute potassium chloride acutely affects vascular function by ingestion via a salted soup. Furthermore we want to get insights on the pathophysiology by analyzing metabolism and cell function in relation to vascular reaction.

Detailed Description
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Some of the leading death causes in western countries are attributed to artheriosclerosis with its consequences especially cardiovascular events. Beside lifestyle risk factors such as physical inactivity, adipositas and stress, high dietary sodium intake is one of the easiest modifiable factors to reduce development and progession of artheriosclerosis. Unfortunately high sodium diet is one of the hallmarks of western diet. Epidemiologic and experimental data have provided compelling evidence that high salt and its induced elevation in bloodpressure is an important factor in the development and progression of cardiovascular disease, artheriosclerosis with its endorgan failure. To analyze the reasons for the hazardous effects of high oral sodium chloride exposure on vascular damage and a possible protective mechanism by the salt substitute potassium chloride, we intend to conduct a single-center randomized trial (ESCAPE-SALT). We aim to measure vascular function by flow mediated dilation (FMD) and dynamic vessel analysis (DVA) of retinal mircocirculation. Participants will be divided into 3 groups. Each group will be served a soup with different salt content. The salt composition is as follows: soup A (9 g sodium chloride), soup B (6 g sodium chloride plus 3 g potassium chloride), and soup C (6 g sodium chloride). The effects on blood pressure, body composition markers, electrolytes, inflammatory and metabolic response, and vascular function are measured before, 4 and 24 h after ingestion of the soup. Furthermore we will investigate the underlying mechanism by performing metabolomic, transcriptomic and proteomic anyalysis.

Official Title
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Effects of Sodium Chloride or Its Substitute Salt Potassium Chloride on Vascular Function and Immune Response - a Randomized Controlled Trial

Conditions
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Vascular Function, Healthy, Diabetes

Intervention / Treatment
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* Dietary Supplement: Soup


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: full-aged signed informed consent no dietary restrictions access to retina for microvascular measurement Exclusion Criteria: age <18 y no retinal access for microvascular measurement known glaucoma antibiotic therapy within the last 4 weeks immunosuppressive Therapie within the last 4 weeks (e.g. glucocorticoids) s.p. malignancy unknown fever within the last 4 weeks salt wasting syndroms (e.g. renal tubular acidosis, Diabetes insipidus) chronic kidney disease stage 4-5 known electrolyte disorder (e.g. hyperkalaemia, hypokalaemia, hypernatriaemia, hyponatriaema) no or rejected informed consent

Ages Eligible for Study
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Minimum Age: 18 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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: high salt group<br>Intake of 9 g sodium chloride | Dietary Supplement: Soup<br>* Intake of a single soup with different sodium chloride and potassium chloride content<br>|
| Active Comparator: low salt group<br>Intake of 6 g sodium chloride | Dietary Supplement: Soup<br>* Intake of a single soup with different sodium chloride and potassium chloride content<br>|
| Active Comparator: substitution group<br>Intake of 6 g sodium chloride plus 3 g potassium chloride | Dietary Supplement: Soup<br>* Intake of a single soup with different sodium chloride and potassium chloride content<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium chloride on retinal vessel diameter and the flicker-light-induced retinal vessel dilatation. | Flicker-induced dilatation and diameter of fundus vessels will be measured via funduscopy in a static an dynamic analysis before, 4 hours and 24 hours after ingestion of a salty soup and the change between the timepoints will be analyzed. First the diameter of venoles and arterioles in µm and their ratio are measured in a standardized fundus picture. In a second step we will film the fundus during three flicker-light periods of 20 seconds and measure the dilatation in percent during the flicker period. | Baseline, 4 hours, 24 hours | 
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium chloride on hypoxia-induced dilatation of brachial artery. | Flow mediated dilatation (FMD) as a marker for macrovascular function will be measured at baseline, 4 hours and 24 hours after ingestion of a salty soup. We will measure FMD by ultrasound based measurement of brachial artery diameter in mm before and after induced hypoxia for 5 minutes. The change of dilatation in percentage between the different timepoints will be analyzed. | Baseline, 4 hours, 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium chloride on mitochondrial respiration capacity in PBMC. | Analysis of mitochondrial respiration capacity via seahorse technology in isolated PBMC from baseline, 4 and 24 hours after salt intake. The oxygen consumption rate (OCR) will be measured and the changes between the timepoints will be analyzed. | Baseline, 4 hours, 24 hours | 
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium chloride on NO metabolism in serum and red blood cells. | We will measure the amount of nitrite and nitrate in red blood cells and serum by gas chemiluminescence at baseline, 4 and 24 hours after salt intake. The change between the three timepoints will be measured. | Baseline, 4 hours, 24 hours | 
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium on metabolic profile in PBMC and plasma. | We will investigate the effect of a single oral high-sodium chloride load or a partial substitution by potassium on the metabolic profile in PBMCs and theplasma. The metabolites will be measured by liquid chromotagraphy and high resolution tandem mass spectrometry at baseline, 4 hours and 24 hours after salt intake. The difference between the timepoints will be analyzed. | Baseline, 4 hours, 24 hours | 
| Effect of a single oral high-sodium chloride load or a partial substitution by potassium on systemic inflammation markers. | Inflammatory markers such as cytokines will be meassured at baseline, 4 and 24 hours after salt intake by ELISA and OLINK. Changes of these markers between the three timepoints will be analyzed. | Baseline, 4 hours, 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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potassium chloride, sodium chloride, microcirculation