The Influence of High and Low Salt on Exosomes in the Urine

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Dietary Supplement: High salt diet followed by low salt diet; Dietary Supplement: Low salt diet followed by high salt diet

• Registration Number: NCT02823613
• Lead Sponsor: University of Southern Denmark

Brief Summary

The hypothesis is that changes in the epithelial sodium channel (ENaC) in the kidney is reflected in urinary exosomes and that the amount of ENaC as well as the cleavage degree is upregulated in conditions with low salt.

Detailed Description

Methods:

Exosomes will be isolated from spot urine by ultracentrifugation and tested using western blotting. In-house developed antibodies against different parts of the ENaC gamma subunit as well as commercial antibodies will be used. A marker for exosomes will validate the presence of exosomes in the urine.

Power considerations:

In this cross over salt-intervention study with quantification of ENaC the investigators refer to a published study regarding the sodium-chloride co-transporter (NCC) in the kidney, were rats where given aldosterone infusion or a low salt diet. In this study n=6 was sufficient to detect a 2-3 fold change in NCC in urinary exosomes. Furthermore 5 patients with primary aldosteronism had a significant increase in NCC in urinary exosomes (N. Lubbe et al, Hypertension 2012).

On the basis of this the investigators choose to test 10 persons, but are not able to make a regular power calculation.

Study Timeline

• Study First Submitted: 2016-06-23
• Study First Submitted QC: 2016-06-30
• Study First Posted: 2016-07-06
• Study Start: 2016-08
• Primary Completion: 2019-05-01
• Study Completion: 2019-05-23
• Status Verified: 2020-04
• Last Update Submitted: 2020-04-06
• Last Update Posted: 2020-04-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 10

Inclusion Criteria

• Healthy men aged 20-40
• Body Mass Index (BMI, weight/height^2) between 18 and 25.

Exclusion Criteria

• Increased blood pressure (hypertension) or in treatment for high blood pressure
• Diabetes
• Regular medical intake
• Smoking
• Expectation of lacking cooperation or lack of understanding of the experiment
• Clinical relevant organic or systemic disease including malign disease
• Decreased kidney function

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Healthy male test subjects 1-5	High salt diet followed by low salt diet	High salt diet followed by low salt diet
Healthy male test subjects 6-10	Low salt diet followed by high salt diet	Low salt diet followed by high salt diet

Primary Outcome Measures

Name	Time	Method
Changes in epithelial sodium channel (ENaC) appearance in urinary exosomes	After 5 days on high or low salt diet	Semiquantitative western blotting

Secondary Outcome Measures

Name	Time	Method
Renin	Before study start and after 5 days on high or low salt diet	Concentration in plasma.
Plasma aldosterone	Before study start and after 5 days on high or low salt diet	Concentration in plasma.

Trial Locations

Locations (1)

University of Southern Denmark; 🇩🇰 Odense, Denmark