Effect of Vitamin D Repletion on Insulin Resistance and Systemic Inflammation
试验速览
- 阶段
- 2 期
- 状态
- 已完成
- 入组人数
- 19
- 试验地点
- 1
- 主要终点
- Percent Change in Hepatic Insulin Sensitivity
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 21 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •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
排除标准
- •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
研究组 & 干预措施
Vitamin D
Participants received weekly oral vitamin D drops using a weight-based calculated dosage for up to six months.
干预措施: Vitamin D (Drug)
Placebo
Participants received weekly oral placebo drops (similar in taste and appearance to vitamin D) for up to six months.
干预措施: Placebo (Drug)
结局指标
主要结局
Percent Change in Hepatic Insulin Sensitivity
时间窗: 2nd clamp visit (after up to 3 months) and 3rd clamp visit (after up to 6 months)
Endogenous glucose production (EGP) was assessed at each study visit to evaluate hepatic insulin sensitivity. Percent change between the EGP at baseline and second visit (after treatment for up to 3 months with Vitamin D to reach a target level of ≥30 ng/ml), and baseline and third visits (after treatment for up to 6 months with Vitamin D in order to reach a target level of ≥50 ng/ml) will be calculated.
次要结局
- Percent Change in Peripheral Glucose Uptake(2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months))
- Evaluated Expression of Pro-inflammatory Gene IL-6(2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months))
- Evaluated Expression of Pro-inflammatory Gene iNOS(2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months))
- Evaluated Expression of Pro-inflammatory Gene TNF-α(2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months))
- Evaluated Expression of Pro-inflammatory Gene PAI-1(2nd clamp visit (up to 3 months) and 3rd clamp visit (up to 6 months))
研究者
Meredith Hawkins
Professor of Medicine (Endocrinology)
Albert Einstein College of Medicine