Metabolic and Vascular Response to Exercise in Sickle Cell Trait Carriers: Effect of Hot Environment
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 21
- 试验地点
- 2
- 主要终点
- Microvascular function
研究概览
简要总结
The heterozygous form of sickle cell disease is clinically asymptomatic. Nevertheless, it was observed that, the sickle cell trait is associated with serious medical complications especially during intense physical efforts. Moreover, the exposure to a hot environment (tropical climate) is suspected to be a determining factor in the occurrence of these medical complications.
However, the relationship between sickle cell trait and death during effort is not well established. Furthermore, the cascade of events that usually cause sickle cell crisis such as red blood cells sickling and rhabdomyolysis and which affect microcirculation are not known.
Our main objective in this study is to verify whether young healthy active men with sickle cell trait have reactive hyperemia to their hemoglobinemic condition during exercise; to identify the contribution of hot environment on these possible disturbances; and to determine underlying mechanisms.
In addition, disturbances in the regulation of glucose metabolism in healthy subjects under hot environment have been reported, marked by a significant increase in postprandial blood glucose. Therefore, this project is also intended to assess the contribution of the disturbance of glycoregulation during exercise under hot environment in active sickle cell trait carriers. The imbalance of pro and anti oxidant agents, the adhesion and inflammation markers will also be evaluated.
Results of this study will allow a better understanding of physio-pathological mechanisms leading to vascular accidents during exercise under tropical climate in young healthy sickle cell trait carriers; and to identify physical activity programs and nutritional interventions adapted to patients with sickle cell disease under hot environment.
详细描述
Introduction
The sickle cell disease is an inherited disorder characterized by abnormal hemoglobin called hemoglobin S or sickle hemoglobin in red blood cells of subjects. The homozygous form (hemoglobin SS) causes sickle cell anemia and is the most severe kind of sickle cell disease. Hemoglobin SC disease and hemoglobin Sβ thalassemia are two other common forms of sickle cell disease. The sickle cell trait carriers are person who inherited the hemoglobin S from one parent and a normal hemoglobin A from the other (heterozygous AS). These people are generally healthy. However, more and more cases of serious complications have been reported, especially during efforts and stays at high altitude like hemorheological and microcirculatory disturbances, and rhabdomyolysis. Increased percentage of red cell sicking was observed in sickle cell trait (AS) carriers compared to normal individual after 45 min of walking at 33°C of temperature. AS individuals also showed an impairment in red blood deformability at rest, at the end, and 24 hours after maximal exercise as compared to normal individuals AA, showing the vulnerability of red blood cells of these seemingly healthy subjects. The stiffness of red blood cells along with blood viscosity also increased in AS group compared to AA group, as consequence the risk of vascular accidents increases. In athletes and military warfighters, an exercise collapse and sudden death associated with sickle cell trait has been observed. Several cases of sudden death in AS individuals have been reported by many authors during exercise, however the exact causes remain very poorly understood.
As constraints related to exercise in tropical climate, it was observed a reduction of power and volemia due to dehydration, diversion of blood volume to the cutaneous territories. It was also reported an impairment of carbohydrate metabolism.
Our objectives in this work are:
- To characterize the microvascular response to exercise in a hot environment in sickle cell trait active young adults,
- To highlight biological mechanisms underlying any microvascular response specificities of the sickle cell trait carriers,
- To describe the vascular consequences of postprandial metabolic disturbances induced by exercise in hot environment,
- To understand fasting and post-prandial glucose metabolism at rest, during and after exercise,
- To test the recovery in a neutral thermal environment (22 °C) as a means of normalizing post-exercise vascular function.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Screening
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 30 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •BMI between 19 and 25kg/m2,
- •Be living in the Caribbean for at least 6 months health
- •Be physically active (≥ 1350 METs/week)
- •No history of heat stroke during exercise
- •No taking any medications
- •Not regularly consuming alcohol
- •Have the ability and willingness to issue consent written, free and enlightened
排除标准
- •Have any other hemoglobinemic status than AA or AS.
- •Weight gain or loss of more than 2 kg in the last 6 month.
- •Food allergy to any of ingredients coming into the composition of test meals or that may result from a cross-contamination during manufacture: eggs and eggs products, gluten, milk and milk-based products (including lactose), soybean and soy products, fruit hulls (almonds, hazelnuts, walnuts, cashew nuts, pecan, macadamia, Brazil, Queensland, pistachios) and products made of these fruits.
- •Monitoring a particular diet
- •Any chronic metabolic pathology, cardiovascular, neurovascular, renal, respiratory, neuromuscular, musculoskeletal or articular known
- •Any disorder of the ear (infections, tumors, perforated eardrums, polyps)
- •Any infectious disease or inflammatory and infectious condition
研究组 & 干预措施
AS and AA
Participants will be submitted to 45 minutes of exercise on ergocycle.
干预措施: Exercise on ergocycle (Other)
结局指标
主要结局
Microvascular function
时间窗: 2 hours
Reactive hyperemia index (arbitrary units) will be assessed at rest, during exercise and during recovery in hot and thermoneutral environment
次要结局
- Oxidative stress(3 months)
- Oxydative stress marker(3 months)
- Hemorheology(24 hours)
- Inflammation(3 months)
- Adhesion molecules(3 mois)
- Rhamdomyolysis(3 months)
研究者
Sophie Antoine-Jonville
Director
University of the French West Indies and French Guiana