Clinical trial NCT01354964: Effect of Vitamin D Repletion on Insulin Resistance and Systemic Inflammation
Official title: Effect of Vitamin D Repletion on Insulin Resistance and Systemic Inflammation
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Insulin Resistance
Keywords: Glucose Metabolism Disorders
Insulin Resistance
Endocrine System
Vitamin D
Lead sponsor: Albert Einstein College of Medicine
Sponsor class: OTHER
Collaborators: name: National Center for Research Resources (NCRR)
First posted: 2011-05-17
Enrollment: 19
Sex: ALL
Minimum age (years): 21
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this research is to study the effects of Vitamin D supplementation on the body's response to insulin (a hormone that controls blood sugar), on inflammation, and on specific cells and processes in fat tissue.

Detailed description: Over the last several years, studies have shown that low vitamin D levels may increase risk of developing Type 2 Diabetes. The investigators will administer vitamin D3 (cholecalciferol) to non-diabetic, insulin resistant subjects with vitamin D deficiency (total vitamin D levels \<20 ng/ml) to increase the level of vitamin D3. The investigators will study the effects of increased Vitamin D on insulin action, adipose tissue inflammation, and on certain cells and processes in fat tissue.

Investigators will study participants with a procedure called a "pancreatic clamp" study. During the clamp procedure, glucose (a sugar) and insulin (a hormone produced in the pancreas that regulates the amount of glucose in the blood) are infused with an intravenous catheter, and blood samples are collected periodically throughout the procedure to measure blood sugar levels and the levels of several hormones that are found in the body and are related to glucose metabolism. Adipose tissue inflammation will be measured using the following inflammatory markers: IL-6, PAI-1, TNF-alpha, and iNOS.

Eligibility criteria: Inclusion Criteria:

* Serum 25(OH)D\<20ng/ml
* Insulin Resistant based on HOMA-IR score of \>3
* Able and willing to provide informed consent
* BMI 20-35

Exclusion Criteria:

* HIV/AIDS
* History of any cancer
* Sarcoidosis
* Alcohol or substance abuse
* Cushing's syndrome
* Primary hyperparathyroidism
* Nephrolithiasis
* Pregnancy or breastfeeding
* Regular visits to a tanning salon
* Hypercalcemia or hypocalcemia
* Untreated or uncontrolled hypertension
* Any chronic illness requiring medication, other than arthritis, hypertension and hyperlipidemia

Primary outcomes:
measure: Percent Change in Hepatic Insulin Sensitivity
timeFrame: 2nd clamp visit (after up to 3 months) and 3rd clamp visit (after up to 6 months)
Secondary outcomes:
measure: Percent Change in Peripheral Glucose Uptake
timeFrame: 2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months)
measure: Evaluated Expression of Pro-inflammatory Gene TNF-α
timeFrame: 2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months)
measure: Evaluated Expression of Pro-inflammatory Gene IL-6
timeFrame: 2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months)
measure: Evaluated Expression of Pro-inflammatory Gene iNOS
timeFrame: 2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months)
measure: Evaluated Expression of Pro-inflammatory Gene PAI-1
timeFrame: 2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months)
Other outcomes:
Locations:
city: Bronx
country: United States
facility: Albert Einstein College of Medicine
state: New York
Study officials:
affiliation: Albert Einstein College of Medicine
name: Meredith A Hawkins, M.D., M.S.
role: PRINCIPAL_INVESTIGATOR
References: