Vitamin D Binding Protein (Gc) Allele Variation Effects Response to Vitamin D Treatment - Full Text View

Sponsored by:	Creighton University
Information provided by:	Creighton University
ClinicalTrials.gov Identifier:	NCT00650780

Purpose

We have just completed a randomized, clinical trial of 100,000 IU Vitamin D3 given as a single dose at the beginning of winter. We found a wide range of responses to the dose. This study proposes that genetic differences account for some of the variation in response of 25(OH)D levels after treatment with oral Vitamin D.

Condition
Vitamin D Status

Study Type:	Observational
Study Design:	Cohort, Cross-Sectional
Official Title:	Vitamin D Binding Protein (Gc) Allele Variation Effects Response to Vitamin D Treatment

Resource links provided by NLM:

Drug Information available for: Vitamin D

U.S. FDA Resources

Further study details as provided by Creighton University:

Primary Outcome Measures:

Gc concentration and phenotype [ Time Frame: at 1st visit ] [ Designated as safety issue: No ]

Biospecimen Retention: None Retained

Biospecimen Description:

Enrollment:	29
Study Start Date:	October 2007
Study Completion Date:	January 2008
Primary Completion Date:	January 2008 (Final data collection date for primary outcome measure)

Groups/Cohorts
1 All of the subjects will have measurements of Gc concentration and phenotype

Detailed Description:

We suspect that the wide range of response is effected by other factors such as variation in Vitamin D binding protein (the major transporter of Vitamin D metabolites). Gc, also known as Vitamin D binding protein (DBP), group specific component, or Gc globulin, is a 52-58 kDa multifunctional plasma protein, synthesized in the liver. The gene encoding for Gc is located on chromosome 4, and three common co-dominant alleles give rise to three phenotypes (Gc1s, Gc1f, and Gc2). Gc binds actin, recruits neutrophil leukocytes and converts into a macrophage- and osteoclast- activating factor. It also is the major transporter of Vitamin D and its' metabolites. Lauridsen et al. showed that Gc phenotype correlates with 25(OH)D levels in a group of postmenopausal women. This study proposes that Gc phenotype accounts for some of the variation in response of 25(OH)D levels after treatment with oral Vitamin D.

Eligibility

Ages Eligible for Study:	19 Years to 90 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes
Sampling Method:	Non-Probability Sample

Study Population

This study will include thirty males and females who took part in a previous study of a single oral dose of vitamin D.

Criteria

Inclusion Criteria:

Must be willing to participate with an additional blood draw.
Must have been in the previous study.

Exclusion Criteria:

Will not be eligible if not a part of the previous study

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00650780

Locations

United States, Nebraska
Creighton University
Omaha, Nebraska, United States, 68131

Sponsors and Collaborators

Creighton University

Investigators

Principal Investigator:

Laura Armas, MD

Creighton University

More Information

No publications provided

Responsible Party:	Creighton University ( Laura Armas )
Study ID Numbers:	Creighton4
Study First Received:	March 30, 2008
Last Updated:	April 1, 2008
ClinicalTrials.gov Identifier:	NCT00650780 History of Changes
Health Authority:	United States: Institutional Review Board

Keywords provided by Creighton University:

Viatmin D, 25-hydroxyvitamin D, Vitamin D binding protein

Study placed in the following topic categories:

Vitamin D
Vitamin D2
Ergocalciferol
Vitamins
Ergocalciferols

Trace Elements
Bone Density Conservation Agents
Calciferol
Micronutrients
Hydroxycholecalciferols

Additional relevant MeSH terms:

Vitamin D
Growth Substances
Vitamins
Physiological Effects of Drugs

Ergocalciferols
Bone Density Conservation Agents
Micronutrients
Pharmacologic Actions

ClinicalTrials.gov processed this record on September 11, 2009