Optimization of Selenoprotein P in Chinese Subjects

Not Applicable

Completed

• Conditions: Selenium Deficiency
• Interventions: Dietary Supplement: 40 µg selenium; Dietary Supplement: 60 µg selenium; Dietary Supplement: 80 µg selenium; Dietary Supplement: 100 µg selenium; Dietary Supplement: 120 µg selenium; Dietary Supplement: placebo; Dietary Supplement: 20 µg selenium

• Registration Number: NCT00428649
• Lead Sponsor: Vanderbilt University

Brief Summary

The purpose of this study is to determine the amount of selenium as selenomethionine that is required to optimize selenoprotein P in selenium-deficient Chinese subjects

Detailed Description

Selenium is an essential nutrient. The Recommended Dietary Allowance (RDA) for selenium is considered to be the amount required to optimize plasma selenoproteins. There are two selenoproteins present in the plasma: selenoprotein P (Se-P) and glutathione peroxidase 3 (GPX-3). Although the amount of selenium required to optimize GPX-3 has been determined, the amount required to optimize Se-P in the plasma remains unknown. We aim to determine this amount by supplementing selenium deficient subjects with varying amounts of selenium as selenomethionine.

The study will take place in Mianning County, China, where selenium status is low. Approximately 150 people will be screened for eligibility to participate in this study. 98 subjects will be enrolled. Background information obtained from each participant will be: age, height, weight and smoking status.

Subjects will be randomized to a selenium supplement group. The selenium supplement will contain either 0, 20, 40, 60, 80, 100, or 120 µg of selenium as selenomethionine. A CDC worker will visit each participant daily to give them their selenium supplement. The CDC worker will watch them take their supplement and will ask if they have any unanticipated problems. Blood samples of 20 ml will be obtained at weeks 0, 4, 8, 12, 16, 20, 24, 32, and 40. Hair samples and 24-hr urine collections will be obtained at 0, 20 and 40 weeks. The total study duration is 40 weeks.

Study Timeline

• Study First Submitted: 2007-01-25
• Study First Submitted QC: 2007-01-25
• Study First Posted: 2007-01-30
• Study Start: 2007-03
• Primary Completion: 2007-12
• Study Completion: 2008-10
• Status Verified: 2012-03
• Last Update Submitted: 2012-03-06
• Last Update Posted: 2012-03-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 98

Inclusion Criteria

• aged 17 years or older
• healthy
• resident of Mianning County for at least 1 year
• hematocrit (PCV) of 30 or greater

Exclusion Criteria

• subject has taken selenium supplements within the year prior to study
• subject plans to relocate during study

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
2	40 µg selenium	40 µg selenium as selenomethionine
3	60 µg selenium	60 µg selenium as selenomethionine
4	80 µg selenium	80 µg selenium as selenomethionine
5	100 µg selenium	100 µg selenium as selenomethionine
6	120 µg selenium	120 µg selenium as selenomethionine
7	placebo	placebo
1	20 µg selenium	20 µg selenium as selenomethionine

Primary Outcome Measures

Name	Time	Method
Plasma selenoprotein P levels at 0, 4, 8, 12, 16, 20, 24, 32, and 40 weeks	40 weeks

Secondary Outcome Measures

Name	Time	Method
Total plasma selenium concentrations at 0, 4, 8, 12, 16, 20, 24, 32, and 40 weeks	40 weeks
Plasma glutathione peroxidase activity at 0, 4, 8, 12, 16, 20, 24, 32, and 40 weeks	40 weeks
24hr urinary selenium excretion at 0, 20 and 40 weeks	40 weeks
Hair selenium levels at 0, 20 and 40 weeks	40 weeks

Trial Locations

Locations (1)

Sichuan Center for Disease Control and Prevention (Sichuan CDC); 🇨🇳 Chengdu, Sichuan, China