Clinical trial NCT01399151: Assessment of Vitamin D Supplementation and Immune Function
Official title: Assessment of Vitamin D Supplementation and Immune Function
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Vitamin D Deficiency
Keywords: Vitamin D
Immune function
Lead sponsor: USDA, Western Human Nutrition Research Center
Sponsor class: FED
First posted: 2011-07-21
Enrollment: 23
Sex: ALL
Minimum age (years): 20
Maximum age (years): 49
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Hypothesis:

Volunteers with vitamin D insufficiency (serum 25(OH)D 25-50 nmol/L) given intermediate or high dose vitamin D supplements (2,000 or 5,000 IU per day) will have increased production of anti-bacterial peptides and interleukin-1, decreased production of other pro-inflammatory cytokines, increased production of regulatory cytokines and an enhanced T- and B-cell response to a tetanus vaccine compared to vitamin D insufficient subjects given low dose vitamin D supplements (400 IU per day).

Detailed description: Specific Aim 1:

Determine if high dose vitamin D supplements decrease the production of proinflammatory and increase the production of regulatory cytokines and chemokines by innate immune cells stimulated ex vivo.

Specific Aim 2:

Determine if high dose vitamin D supplements decrease serum markers of inflammation and increase serum and cellular levels of defensive molecules (e.g., cathelicidin).

Specific Aim 3:

Determine if high dose vitamin D supplements decrease blood levels of proinflammatory T-helper type 1 (Th1) and Th17 cells and increase levels of anti-inflammatory T-regulatory (Treg) and Th2 cells.

Specific Aim 4:

Determine if high dose vitamin D supplements increase antigen specific T cell and B cell responses after tetanus vaccination.

Eligibility criteria: Inclusion Criteria:

* Age 20-49 (men) and 20-45 (women)
* BMI 18.5-30
* Serum 25OH Vitamin D 25-50 nmol/L

Exclusion Criteria:

* Pregnant or nursing women
* Daily smoker
* Anemia (Hgb\<12 mg/dL for women and \<13 mg/dL for men) determined at initial visit
* Any report or diagnosis of disease or chronic condition that may affect vitamin D absorption such as cystic fibrosis, celiac disease, surgical removal of part of the stomach or intestines, and some forms of liver disease
* Diagnosis of hyper parathyroidism and chronic granulomatous disease, which increases risk of hypercalcemia.
* Planned to travel to a location at which either altitude or latitude would result in significant vitamin D synthesis during the study period.
* Not previously vaccinated with TT, or vaccinated within five years
* Use of steroids or antibiotics within the past 4 weeks
* Current use of nutritional supplements that may alter immune function such as omega 3 fatty acid supplements
* Current use of anti-inflammatory or anti-convulsion medications
* Self reported history of significant adverse response to previous vaccinations

Primary outcomes:
measure: Change in Cathelicidin levels in granulocytes
timeFrame: 0, 8, and 12 weeks
measure: Change in cytokine levels from stimulated Periferal Blood Mononuclear Cells
timeFrame: 0, 8 and 12 weeks
measure: Change in serum cytokines and acute phase proteins
timeFrame: 0, 8 and 12 weeks
measure: Change in markers of response to tetanus vaccination
timeFrame: 0, 8, 9, 10 and 12 weeks
measure: Change in serum 25OH Vitamin D
timeFrame: 0, 4, 8, and 12 weeks
measure: Change in urinary calcium-to-creatinine ratio
timeFrame: 0, 2, 4, 6, 8 and 10 weeks
Secondary outcomes:
measure: Change in level of 5-lipoxygenase protein in granulocytes
timeFrame: 0, 8 and 12 weeks
measure: Change in production of leukotrienes in granulocytes
timeFrame: 0, 8, and 12 weeks
Other outcomes:
Locations:
city: Davis
country: United States
facility: Western Human Nutrition Center, University of California Davis
state: California
Study officials:
affiliation: WHNRC, ARS, University of California Davis
name: Charles Stephensen, PhD
role: PRINCIPAL_INVESTIGATOR
References: