Effect of a Grape Seed Extract (GSE) on Insulin Resistance
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 19
- 试验地点
- 1
- 主要终点
- Changes in insulin resistance
研究概览
简要总结
In people with the metabolic syndrome, the investigators hypothesize that administration of a single 300 mg dose of a grape seed extract (GSE) will reduce insulin resistance (how well cells in the body can take up and use glucose), oxidative stress, and the amount of oxidized LDL in the blood during a 24 hour period. These measurements will be assessed at hourly intervals during the 24 hour study day protocol. Additionally, the investigators hypothesize that daily administration of 300 mg of GSE for 30 days will decrease baseline insulin resistance, oxidative stress, and the level of oxidized LDL in the blood.
详细描述
In people with the metabolic syndrome, the investigators hypothesize that administration of a single 300 mg dose of a grape seed extract (GSE) will reduce insulin resistance (how well cells in the body can take up and use glucose), oxidative stress, and the amount of oxidized LDL in the blood during a 24 hour period. Each of these can be elevated after eating high fat meals, which are commonly found in the average Western diet. To better assess the impact of these high fat eating patterns, three standardized high fat meals will be served during the study day: breakfast, lunch, and dinner. Measurements in the blood will be assessed at hourly intervals during the 24 hour study day protocol. Additionally, the investigators hypothesize that daily administration of 300 mg of GSE for 30 days will decrease baseline insulin resistance, oxidative stress, and the level of oxidized LDL in the blood when this 24 hour study day protocol is repeated and breakfast, lunch, and dinner are again served.
Insulin resistance will be measured using a comparison of insulin and glucose levels in the blood. Oxidative stress, a measure of inflammation, will be measured by cytokines levels in the blood. The level of oxidized LDL will be measured in the blood. The investigators also plan to undertake a subsidiary pharmacokinetic study on the various polymers which are known to be present in grape seed extracts to determine their bio-availability and their relationship to the biological effects observed.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 20 Years 至 70 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Metabolic Syndrome, based on subject meeting at least 3 of the following criteria:
- •Abdominal obesity with waist circumference > 40 inches in men or > 35 inches in women,
- •Pre-hypertension with blood pressure > 135/85,
- •Fasting blood glucose levels above 110 mg/dl,
- •Plasma triglyceride levels in excess of 150 mg/dl,
- •HDL levels below 40 mg/dl in men or 50 mg/dl in women.
排除标准
- •Any known systemic disease,
- •Diabetes,
- •Alcohol consumption > 1-2 drinks/week,
- •Taking any medications or supplements that will affect metabolism, their ability to exercise or oxidative status,
- •Female subjects having abnormal menstrual cycles, taking oral contraceptives, pregnant or lactating.
研究组 & 干预措施
Placebo
This is a 30 day arm. At the baseline study visit, subjects will consume one placebo (maltodextrin) capsule followed by 3 high fat meals: breakfast, lunch, and dinner. Blood will be drawn at specified intervals throughout the day. Flow mediated dialysis will be performed before breakfast and again 1.5 hours later, after capsule consumption and breakfast. A minimum 14 day washout period will be between arms if this is the first arm in the randomized cross-over.
干预措施: Placebo (Dietary Supplement)
Grape Seed Extract
This is a 30 day arm. At the baseline study visit, subjects will consume one 300 mg capsule of MegaNatural Gold followed by 3 high fat meals: breakfast, lunch, and dinner. Blood will be drawn at specified intervals throughout the day. Flow mediated dialysis will be performed before breakfast and again 1.5 hours later, after capsule consumption and breakfast. A minimum 14 day washout period will be between arms if this is the first arm in the randomized cross-over.
干预措施: Grape Seed Extract (Dietary Supplement)
结局指标
主要结局
Changes in insulin resistance
时间窗: Baseline and 30 days
Insulin resistance will be assessed by comparing the baseline fasting insulin concentration to the fasting insulin concentration after intervention period of 30 days; the Homeostatic Model Assessment (HOMA) value will be utilized for comparisons.
次要结局
- Changes in oxidative stress(Baseline and 30 days)
- Changes in oxidized LDL (oxLDL) concentrations(Baseline and 30 days)
- Changes in vascular stress(Baseline and 30 days)
- Changes in insulin response(Baseline and 30 days)
- Changes in oxidized LDL (oxLDL) concentrations(Baseline and 24 hour post-prandial response)
- Changes in oxidative stress(Baseline and 24 hour post-prandial response)
- Changes in vascular stress(Baseline and 1 hour post-prandial)
- Changes in insulin response(Baseline and 24 hour post-prandial response)