The Effect of 4 Weeks of L-Citrulline Supplementation on Macro- and Microvascular Function in Type 2 Diabetes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 36
- 试验地点
- 1
- 主要终点
- Change in microvascular endothelial function in the fasted condition
研究概览
简要总结
The purpose of this study is to examine the effect of 4 weeks of Citrulline supplementation on macro- and microvascular function during acute hyperglycemia in middle-aged and older adults with type 2 diabetes.
详细描述
Using a double-blind, randomized, placebo-controlled, and cross-over design, middle-aged and older adults with type 2 diabetes will be randomized to receive either CIT supplementation (6g/day) or placebo (Microcrystalline Cellulose, 6g/day) for 4 weeks.
There will be a total of 5 laboratory visits. Visit 1 (screening visit) will take approximately 1 hour and 30 minutes, visit 2 will take approximately 2 hours and 30 minutes, and visits 3-5 will be approximately 3 hours each.
Visit 1 will measure blood pressure, blood glucose and lipid levels, anthropometry, body composition, and muscle strengths. Visits 2-5 will assess vascular function and glucose control during fasted and acute hyperglycemia conditions induced by 75g of glucose ingestion.
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
- Double (Participant, Investigator)
盲法说明
Double-blind (subject, investigator), randomized, cross-over, placebo-controlled
入排标准
- 年龄范围
- 40 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Middle-aged and older women and men between 40-75 years old
- •A physician diagnosed type 2 diabetes at least 3 months ago
- •Treated with an oral hypoglycemic medication
- •Body mass index < 40 kg/m2
- •Systolic blood pressure < 160 mmHg
- •Sedentary (defined as < 120 min/week of exercise)
- •Not currently participating in exercise or dietary interventions for at least 2 months prior the present study and willing to abstain from participating in those strategies during the duration of this study.
排除标准
- •< 40 years of age and > 65 years of age
- •Use of medications and/or any supplements that may affect outcome variables (such as arginine- or citrulline-containing supplements, nitrates, and nitroglycerin)
- •Body mass index ≥ 40 kg/m2
- •Systolic blood pressure ≥ 160 mmHg
- •Recent changes in medications within 3 months
- •Current smoking any tobacco use
- •Type 1 diabetes, severe cardiovascular/renal/pulmonary diseases
- •More than 7 alcoholic drinks/week of consumption
- •Premenopausal women with an irregular menstrual cycle (oligomenorrhea) or pregnancy
研究组 & 干预措施
Placebo
Microcrystalline cellulose
干预措施: Placebo (Dietary Supplement)
L-citrulline
6 grams/day
干预措施: L-citrulline (Dietary Supplement)
结局指标
主要结局
Change in microvascular endothelial function in the fasted condition
时间窗: 4 weeks
Microvascular endothelial function will be assessed using peripheral arterial tonometry (EndoPAT device) during reactive hyperemia at baseline and after 4 weeks of supplementation.
Change in stroke volume during acute hyperglycemia
时间窗: 4 weeks
Stroke volume will be measured using impedance cardiography (PhysioFlow) at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in blood pressure in the fasted condition
时间窗: 4 weeks
Brachial and aortic blood pressure will be measured using an automated sphygmomanometry arm cuff (SphygmoCor XCEL). Beat-to-beat blood pressure will be measured using an automated photoplethysmography finger cuff (Finometer). Blood pressure will be measured at baseline and after 4 weeks of supplementation.
Change in blood glucose levels in the fasted condition
时间窗: 4 weeks
Blood glucose levels will be measured by finger prick at baseline and after 4 weeks of supplementation.
Change in central and peripheral arterial stiffness in the fasted condition
时间窗: 4 weeks
Arterial stiffness will be assessed using the central (carotid-femoral) and peripheral (femoral-ankle) pulse wave velocity at baseline and after 4 weeks of supplementation.
Change in blood pressure during acute hyperglycemia
时间窗: 4 weeks
Brachial and aortic blood pressure will be measured using an automated sphygmomanometry arm cuff (SphygmoCor XCEL). Beat-to-beat blood pressure will be measured using an automated photoplethysmography finger cuff (Finometer). Blood pressure will be measured at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in macrovascular endothelial function in the fasted condition
时间窗: 4 weeks
Macrovascular endothelial function will be measured using brachial artery flow mediated dilation (ultrasonography) during reactive hyperemia at baseline and after 4 weeks of supplementation.
Change in blood glucose levels during acute hyperglycemia
时间窗: 4 weeks
Blood glucose levels will be measured by finger prick at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in central and peripheral arterial stiffness during acute hyperglycemia
时间窗: 4 weeks
Arterial stiffness will be assessed using the central (carotid-femoral) and peripheral (femoral-ankle) pulse wave velocity at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in stroke volume in the fasted condition
时间窗: 4 weeks
Stroke volume will be measured using impedance cardiography (PhysioFlow) at baseline and after 4 weeks of supplementation.
Change in macrovascular endothelial function during acute hyperglycemia
时间窗: 4 weeks
Macrovascular endothelial function will be measured using brachial artery flow mediated dilation (ultrasonography) during reactive hyperemia at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in microvascular endothelial function during acute hyperglycemia
时间窗: 4 weeks
Microvascular endothelial function will be assessed using forearm muscle oxygenation (near-infrared spectroscopy) during reactive hyperemia at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in total peripheral resistance during acute hyperglycemia
时间窗: 4 weeks
Total peripheral resistance will be measured using impedance cardiography (PhysioFlow) at 60 minutes after oral glucose ingestion at baseline and after 4 weeks of supplementation.
Change in total peripheral resistance in the fasted condition
时间窗: 4 weeks
Total peripheral resistance will be measured using impedance cardiography (PhysioFlow) at baseline and after 4 weeks of supplementation.
次要结局
- Change in serum arginase activity levels(4 weeks)
- Change in 24-hour ambulatory blood pressure monitoring(4 weeks)
- Change in insulin levels(4 weeks)
- Change in serum arginine levels(4 weeks)
- Change in body composition(4 weeks)
- Change in muscle strength(4 weeks)
研究者
Arturo Figueroa
Arturo Figueroa, Principal Investigator
Texas Tech University