Serum 25(OH)D Concentration Clinical Trial
Official title:
The Effect of a High-dose Oral Vitamin D3 Bolus on Serum 25-hydroxyvitamin D3 and Vitamin D Receptor Target Gene Expression (VitDbol)
The purpose of the study is to investigate whether a high-dose vitamin D3 oral bolus (2000 micrograms) produces marked vitamin D receptor target gene expression response and whether there is large inter-individual variation.
Serum 25-hydroxyvitamin D [25(OH)D3] is a well-established marker for vitamin D status of
the human body. In addition to the general importance of vitamin D for bone health, low
serum 25(OH)D3 concentrations have been associated with increased risk of several health
outcomes, such as autoimmune diseases, type 2 diabetes and cardiovascular complications.
However, there is significant inter-individual variation in the average serum 25(OH)D3
concentrations and also in the response to supplementation with vitamin D. Genetic and
epigenetic factors have been suggested to be responsible for a large part of the variation,
but currently there is little information about the health effects of the variation.
In our previous study (VitDmet, Clinicaltrials.gov NCT01479933) we showed that only half of
the participants responded to the 5-month vitamin D3 supplementation of 40 µg/day or 80
µg/day as expected and that certain vitamin D receptor (VDR) target genes were suitable
biomarkers for displaying the transcriptomic response of human tissues to vitamin D3
supplementation.
The purpose of the current study is to investigate whether a high-dose vitamin D3 oral bolus
produces marked VDR target gene expression response and whether there is large
inter-individual variation, as what was suggested with the 5-month lower-dose
supplementation.
In the Trial 1, the subjects are randomized to receive either 2,000 micrograms (80 000 IU)
of vitamin D3 (n=20) or placebo (n=10) in one day. Blood samples are collected for
peripheral blood mononuclear cell isolation and serum 25(OH)D3 measurements at baseline and
24 h and 48 h and 30 days after the first dose. Blood samples are also collected for
immunomarker analyses. In the Trial 2, the procedures of the Trial 1 are repeated in two
subjects with known low and high serum 25(OH)D3 concentrations in order to investigate more
specifically the impact of different starting levels of serum 25(OH)D3.
In February 2015, new subjects were recruited to enter the Trial 1 in order to increase the
size of the study. All the new subjects received the 2,000 microgram bolus of vitamin D3,
there were no new subjects in the placebo arm.
June 30, 2016. Change to protocol: There will be no Trial 2, but instead the blood samples
obtained in the Trial 1 from up to six subjects will be used for the additional analyses.
The subjects are selected based on the response to vitamin D supplementation in the Trial 1.
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Allocation: Randomized, Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Basic Science
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT03537027 -
Efficiency of Vitamin D3 and 25-hydroxyvitamin D3 on Transcriptomic Changes of Low Vitamin D Responders
|
Phase 1 |