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NCT00877812 · ClinicalTrials.gov registry record · NA
Vitamin B6 Dependence of One-Carbon Metabolism
A NA study, sponsored by University of Florida.
- Completed
- Registry status
- NA
- Development phase
- 45
- Enrollment target
NCT00877812: Completed NA study, sponsored by University of Florida.
NCT00877812 is a NA study that has completed, run by University of Florida. The registered enrollment target is 45 participants, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (97% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00877812, a NA study, has completed, sponsored by University of Florida.
- COMPLETED
- Registry status
- NA
- Development phase
- 45 participants
- Enrollment target
Study Summary
Marginal vitamin B6 deficiency, which occurs commonly worldwide, leads to a cellular deficiency of the coenzyme pyridoxal phosphate (PLP). PLP is a coenzyme in several phases of one carbon (1C) metabolism, which is the array of reactions in which one carbon units are acquired and used in reactions including nucleotide synthesis, regeneration of methionine (Met) from homocysteine (Hcy), and methylation of many biological compounds. 1C metabolism is linked to the transsulfuration pathway in which Hcy undergoes PLP-dependent catabolism leading to cysteine, whose availability governs the formation of the antioxidant glutathione. Nutritional or genetic conditions that impair 1C metabolism are associated with elevation in plasma Hcy concentration and increased risk of vascular disease. It is believed that the metabolic effects of vitamin B6 deficiency will be most pronounced following protein intake when the vitamin B6-dependent pathways of amino acid metabolism experience the greatest substrate load. The human subjects protocols of this study consist of two distinct phases intended to extend our understanding of basic human 1C metabolism and the effects of marginal vitamin B6 deficiency under postprandial conditions. Phase 1 will investigate the effects of vitamin B6 nutrition on the PLP-dependent generation of 1C units by the glycine cleavage system and on the synthesis of glutathione. Phase 2 will investigate the dependence of methionine metabolism on vitamin B6 nutritional status, with particular emphasis on the recycling of Hcy to Met. Each phase of this study will involve 14 healthy, nutritionally adequate, young adults (7 male, 7 female) who will undergo metabolite profiling and kinetic analysis using intravenously infused stable isotopic tracers performed both before and after a \~4-week period of dietary vitamin B6 restriction. Subjects will be assigned to either Phase 1 or Phase 2, which will be identical in design except for the tracers and analytical methods u
Primary Outcome
(a) Vitamin B6 deficiency will reduce the rate of glycine turnover and interconversion with serine and will reduce the generation of 1C units by the glycine cleavage system. (b) Vitamin B6 deficiency will yield a reduced in vivo rate of erythrocyte glutathione synthesis.
Interventions
- DIETARY_SUPPLEMENT Arm 1 glycine and leucine
- DIETARY_SUPPLEMENT Arm 2 Intervention of Serine and methionine infusion
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 45 participants |
| Start Date | 2008-01 |
| Est. Completion | 2010-09 |
| Phase | NA |
What the finished NCT00877812 record still lists
NCT00877812 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 45 participants, a relatively small participant target, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (97% lower).
The record links to 0 conditions, and to 2 interventions - of which Arm 1 glycine and leucine is the first listed.
NCT00877812 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00877812 about?
NCT00877812 is a clinical study titled "Vitamin B6 Dependence of One-Carbon Metabolism". Marginal vitamin B6 deficiency, which occurs commonly worldwide, leads to a cellular deficiency of the coenzyme pyridoxal phosphate (PLP). PLP is a coenzyme in several phases of one carbon (1C) metabolism, which is the array of reactions in which one carbon units are acquired and used in reactions i...
What is the current status of trial NCT00877812?
This trial is currently completed. It is a NA study. The enrollment target is 45 participants. The study started on 2008-01. Estimated completion is 2010-09.
What interventions are being tested in trial NCT00877812?
The interventions under investigation include: Arm 1 glycine and leucine (DIETARY_SUPPLEMENT), Arm 2 Intervention of Serine and methionine infusion (DIETARY_SUPPLEMENT).
Who is sponsoring clinical trial NCT00877812?
This trial is sponsored by University of Florida, which has 1,106 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00877812's enrollment target sits among peer trials
45 1411th of 2000 higher than 578 of 2,000 other NA trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other NA trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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