Exercise-induced Erythropoiesis: the Mechanistic of Angiotensin II
试验速览
- 阶段
- 4 期
- 状态
- 招募中
- 入组人数
- 80
- 试验地点
- 1
- 主要终点
- maximal oxygen consumption in ml/kg/min
研究概览
简要总结
The major aims are to determine the effect of acute (single dose) blockade of ANGII receptor 1 (AT1) on the EPO response to a single session of endurance exercise, as well as determine the effect of chronic (8-week) blockade of AT1 on ET-induced adaptations in total circulating red blood volume and hemoglobin.
详细描述
Physical activity, particularly when comprised of endurance training (ET) leading to cardiovascular adaptations, is considered the most effective intervention to augment life expectancy. Major health benefits induced by ET are closely associated (independently of traditional risk factors) with improvements in maximal oxygen consumption (VO2max), a hallmark of aerobic exercise capacity. The higher the VO2max the greater the likelihood to be free of cardiovascular disease, the main cause of mortality worldwide. Understanding the mechanisms explaining the improvement in VO2max with ET can provide sound basis for highly effective lifestyle and pharmacological interventions aimed to enhance cardiovascular health in the general population. So far, the essential role of ET-induced increased formation of red blood cells, i.e., erythropoiesis, has been firmly established for any improvement in VO2max. Yet, the underlying mechanism remains elusive. Clinical studies and recent investigations by the PI point towards the endocrine effects of key hormones that regulate blood volume (BV). Notably, the impact of ET-induced changes in angiotensin II (ANGII), a multifaceted hormone that modulates erythropoiesis through its effects on kidney erythropoietin (EPO) production, has to be experimentally elucidated in humans.
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
Participants will be randomly allocated in a 1:1 ratio to valsartan or placebo. Valsartan and placebo tablets will be indistinguishable in taste, smell, appearance and dosage. The protocol will be developed in a double-blind manner in that both participants and investigators will be blinded toward the intervention condition.
入排标准
- 年龄范围
- 20 Years 至 —(Adult, Older Adult)
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy status, absence of current medical symptoms or medication limiting incremental exercise testing
- •No history of cardiac, pulmonary or kidney disease.
排除标准
- •Individuals fulfilling the above criteria but currently involved in regular exercise training (> 5 hr/week)
研究组 & 干预措施
Valsartan tablets
干预措施: Valsartan 80 mg (Drug)
Placebo tablets
干预措施: Placebo (Drug)
结局指标
主要结局
maximal oxygen consumption in ml/kg/min
时间窗: 10 weeks
Maximal oxygen consumption (VO2max), a hallmark of aerobic capacity, will be determined with continuous measurements of oxgyen uptake using an online gas collection system (Quark CPET, Cosmed, Italy)
stroke volume in ml/m2
时间窗: 10 weeks
Stroke volume (SV) will be determined as left ventricular end-diastolic volume (LVEDV) minus left ventricular end-systolic volume (LVESV)
Blood volume (BV)-regulating hormone: Plasma ANGII in ng/dL
时间窗: 10 weeks
Plasma ANGII concentrations will be quantified by means of established competitive enzyme immunoassays
次要结局
未报告次要终点
