Influence of Hesperidin and Vitamin C on Uric Acid Concentration

Study Overview
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Brief Summary
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Aim of the study is to investigate the impact of hesperidin and/or vitamin C on elevated uric acid concentrations.

Detailed Description
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Duration of the study is 9 weeks. 1) a washout week, 2) two intervention weeks, 3) four weeks washout period, 4) two intervention weeks. The study is conducted under free living conditions. During washout weeks consumption of orange juice or citrus fruits or vitamin C containing supplements is restricted. During intervention weeks 200 mL of study drink is consumed daily. And participants are asked to maintain their normal physical activity and habitual diet. Additional citrus or vitamin C containing beverages are not allowed. At the beginning and the end of each intervention phase uric acid, insulin sensitivity, blood pressure, pulse wave velocity and bioavailability of hesperidin are assessed.

Official Title
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Influence of Hesperidin and Vitamin C on Uric Acid Concentration

Conditions
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Higher Uric Acid Concentrations (>5,5 mg/dl), Healthy

Intervention / Treatment
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* Dietary Supplement: Control
* Dietary Supplement: Hesperidin
* Dietary Supplement: Vitamin C
* Dietary Supplement: Hesperidin + Vitamin C


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy higher uric acid concentration (≥5.5 mg/dL) Informed written consent Exclusion Criteria: pregnancy fructose intolerance smoking gout or medicated hyperuricemia diabetes mellitus antidiabetic or cytostatic medication weight loss (≥5% in the past 3 months) consumption of vitamin C-containing supplements parallel participation in a clinical trial anemia and / or iron deficiency

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Hesperidin (A)<br>study drink without hesperidin and without vitamin C compared to study drink with hesperidin | Dietary Supplement: Control<br>* study drink (two weeks)<br>Dietary Supplement: Hesperidin<br>* study drink + Hesperidin 600 mg (two weeks)<br>|
| Experimental: Hesperidin + Vitamin C (B)<br>study drink with vitamin C compared to study drink with hesperidin and vitamin C | Dietary Supplement: Vitamin C<br>* study drink + Vitamin C 250 mg (two weeks)<br>Dietary Supplement: Hesperidin + Vitamin C<br>* study drink + Hesperidin 600 mg + Vitamin C 250 mg (two weeks)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in uric acid serum concentrations | measured via uric acid serum concentration (mg/dL) | Baseline (pre) and post two weeks of intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in uric acid excretion | measured via uric acid excretion in 24h urine (mg/24h) | Baseline (pre) and post two weeks of intervention | 
| changes in pulse wave velocity | measured via oscillometric method (m/s) | Baseline (pre) and post two weeks of intervention | 
| insulin sensitivity | measured via minimal model from oral glucose tolerance test data using the particular study drink with added glucose to 75 g Glucose / 200 mL | Baseline (pre) intervention periods | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hesperidin, vitamin C, uric acid concentration