2 Weeks of L-Citrulline Supplementation Improves Arterial Function and Systolic Blood Pressure at Rest and During Exercise in Postmenopausal Women With Elevated Blood Pressure and Hypertension
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 19
- 试验地点
- 2
- 主要终点
- Macrovascular endothelial function at rest
研究概览
简要总结
The objective of this project is to elucidate the effect of L-Citrulline (L-CIT) supplementation on vascular function at rest and during rhythmic handgrip exercise and functional sympatholysis via lower-body negative pressure in postmenopausal women with elevated blood pressure and hypertension.
详细描述
Using a double-blind, randomized, placebo-controlled, and crossover design, overweight or obese postmenopausal women with elevated blood pressure (BP) or hypertension will receive CIT (6 grams/day) or placebo for 2 weeks, separated by a two-week washout period.
There will be a total of 5 laboratory visits. The 1st visit will take approximately 1 hour. The 2nd - 5th visits will take about 2 hours and 15 minutes. Visit 1 will be a screening visit, visits 2 and 4 will be considered baseline visits, and visits 3 and 5 will be following the participants' two weeks of supplementation. Arterial stiffness (carotid-femoral and femoral-dorsalis pedis pulse wave velocity) and endothelial function will be assessed at rest. Additionally, brachial artery blood flow, forearm muscle oxygenation, cardiovascular hemodynamics (stroke volume, cardiac output, systemic vascular resistance), and BP will be assessed at rest, during 6 minutes of rhythmic handgrip exercise at 30% of a predetermined maximal voluntary contraction, and 2 minutes of superimposed lower body negative pressure to increase sympathetic activity.
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)
入排标准
- 年龄范围
- 50 Years 至 70 Years（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Postmenopausal women (defined as the absence of menstruation for at least 1 year).
- •Resting systolic blood pressure 120-150 mmHg.
- •Between the ages of 50 - 70 years.
- •Sedentary (< 120 minutes of exercise/week).
- •Body mass index of 25 - 39.9 kg/m
- •Fasting glucose < 126 mg/dL and HbA1c < 6.5%.
排除标准
- •Body mass index ≥ 40 or < 25 kg/m
- •Systolic blood pressure > 150 mmHg.
- •Taking more than two antihypertensive medications.
- •Cardiovascular diseases, type I/II diabetes, musculoskeletal disorders, or cancer.
- •Changes in hypertensive medication in the past three months.
- •Began or changed hormone replacement therapy in the past 6 months.
- •Current smoker.
- •Heavy drinking (> 7 alcoholic drinks/week).
- •Participants on beta-blockers or other vasodilatory supplements (nitrates).
- •Incorporated in a weight loss program and/or aerobic or resistance training program.
结局指标
主要结局
Macrovascular endothelial function at rest
时间窗: 2 weeks of each intervention
Endothelial function will be assessed via brachial artery flow-mediated vasodilation (ultrasonography) during reactive hyperemia at baseline and after 2 weeks of each supplementation.
Brachial artery blood flow at rest and during rhythmic handgrip exercise with and without lower-body negative pressure
时间窗: 2 weeks of each intervention
Blood flow will be measured via Doppler ultrasound before and after 2 weeks of each intervention.
Forearm muscle oxygenation at rest and during rhythmic handgrip exercise with and without lower-body negative pressure
时间窗: 2 weeks of each intervention
Muscle oxygen saturation will be measured via near-infrared spectroscopy before and after 2 weeks of each intervention.
Microvascular endothelial function at rest
时间窗: 2 weeks of each intervention
Endothelial function will be assessed via peripheral arterial tonometry (endoPAT) during reactive hyperemia at baseline and after 2 weeks of each supplementation.
次要结局
- Stroke volume at rest and during rhythmic handgrip exercise with and without lower body negative pressure(2 weeks of each intervention)
- Heart rate at rest and during rhythmic handgrip exercise with and without lower body negative pressure(2 weeks of each intervention)
- Central and peripheral arterial stiffness at rest(2 weeks of each intervention)
- Beat-to-beat blood pressure at rest and during rhythmic handgrip exercise with and without lower-body negative pressure(2 weeks of each intervention)
- Forearm muscle strength(2 weeks of each intervention)
- Nitric oxide levels(2 weeks of each intervention)
- L-citrulline levels(2 weeks of each intervention)
- Aortic hemodynamics at rest and during rhythmic handgrip exercise with and without lower body negative pressure(2 weeks of each intervention)
- Systemic vascular resistance at rest and during rhythmic handgrip exercise with and without lower body negative pressure(2 weeks of each intervention)
- L-arginine levels(2 weeks of each intervention)
- L-ornithine levels(2 weeks of each intervention)
研究者
Arturo Figueroa
Arturo Figueroa, Principal Investigator
Texas Tech University