Low-Salt Diet Effect on Th17-Mediated Inflammation and Vascular Reactivity in Psoriasis

Study Overview
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Brief Summary
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Psoriasis presents an independent cardiovascular risk factor characterized by chronic low-grade systemic inflammation and oxidative stress which altogether might lead to endothelial dysfunction. It has been reported that increased oxidative stress has a pivotal role in high dietary sodium-induced endothelial dysfunction. Previous studies on sodium accumulation in psoriatic skin lesions and the sodium-induced augmentation in Th17 immune response, raise the question on the complex interplay between sodium and psoriasis, especially in the context of cardiovascular morbidity. This study aimed to investigate the effect of a 2-week low-salt diet on endothelium-dependent and endothelium-independent cutaneous microvascular vasodilation and Th17-Mediated Inflammation in patients with psoriasis vulgaris.

Official Title
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Effects of Low Salt Dietary Intake on Th17-Mediated Inflammation and Vascular Reactivity in Patients With Psoriasis

Conditions
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Psoriasis Vulgaris

Intervention / Treatment
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* Other: Low-Salt Diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with diagnosed psoriasis vulgaris subjects do not use topical corticosteroid therapy for at least 2 weeks before inclusion in the study and 2 weeks during the study subjects do not use systemic or biological therapy for at least 3 months before and 2 weeks during the study. Exclusion Criteria: age < 18 years existence of other immune-mediated diseases (with the exception of autoimmune thyroid diseases and psoriatic arthritis - people with these comorbidities can be included) malignant diseases current infectious diseases and allergic reactions within 6 weeks before the start of the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low-Salt Diet<br>Low-salt diet (LS diet) according to DASH eating plan, with sodium intake of 1500 mg (3.75 g of salt), within the period of 14 days | Other: Low-Salt Diet<br>* Low-salt diet (LS diet) according to DASH eating plan, with sodium intake of 1500 mg (3.75 g of salt), within the period of 14 days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microvascular endothelial function | Cutaneous microvascular blood flow will be measured by Laser Doppler Flowmetry in response to vascular occlusion (post occlusive reactive hyperaemia - PORH), in response to iontophoresis of acetylcholine (ACh) and local thermal hyperemia (LTH) before and after LS diet protocol | 2 weeks | 
| Frequency of peripheral T helper 17 (Th17) and regulatory lymphocytes (Treg) among parent lymphocytes sub-population | Flow cytometry assessment of the frequencies of peripheral Treg and Th17 lymphocytes before and after LS diet protocol | 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microvascular non-endothelial function | Cutaneous microvascular blood flow will be measured by Laser Doppler Flowmetry in response to iontophoresis of sodium nitroprusside (SNP) before and after LS diet protocol | 2 weeks | 
| Relative amount of serum- and glucocorticoid-induced kinase 1 (SGK1) in peripheral blood mononuclear cells | Relative amount of total serum- and glucocorticoid regulated kinase 1 (SGK1) in cultured cells will be measured by commercially available cell-based enzyme-linked immuno-sorbent assay (ELISA) kit before and after LS diet protocol | 2 weeks | 
| Serum Protein Concentration of Pro- and Anti-Inflammatory Cytokines | Serum protein concentrations (pg/mL) of pro-inflammatory and anti-inflammatory cytokines will be measured with panel for multiplex protein quantitation before and after LS diet protocol | 2 weeks | 
| 24-hour natriuresis | A 24-h urinary sodium excretion will be measured in each participant before and after LS diet protocol in order to assess compliance to the given dietary protocol | 2 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diet, Sodium-Restricted, Psoriasis, Laser-Doppler Flowmetry, Microcirculation, Endothelium