Cortisol regulation during exercise and obesity in adolescents with Down syndrome

描述(由申请人提供)：唐氏综合症青少年中超重和肥胖的患病率超过50%，明显高于一般人群的超重和肥胖率。这种情况会持续到成年，并有助于发展更多的次级健康状况。因此，肥胖是健康差距的一个主要来源。目前尚不清楚是什么原因导致唐氏综合症青少年肥胖率较高。糖皮质激素(即皮质醇)功能可能是解释这一人群肥胖风险增加的一种新的神经内分泌机制。最近的研究表明，与非残疾成年人相比，患有唐氏综合症的年轻人表现出皮质醇失调。在一般人群中，下丘脑-垂体-肾上腺(HPA)轴和皮质醇功能的失调会促进体重增加和腹部脂肪增加。然而，目前尚不清楚唐氏综合症青少年皮质醇功能的差异是否会导致肥胖率更高。此外，许多针对儿童肥胖的干预措施都涉及运动。运动中正常的皮质醇反应有望对肥胖的发展起到保护作用，但目前尚不清楚运动中的皮质醇反应与唐氏综合症青少年肥胖之间的关系。因此，这项奖学金申请建议研究皮质醇功能如何在两种情况下调节脂肪质量(肥胖)和唐氏综合症之间的联系：1)日常生活在自然环境中；2)对一轮中等强度运动的反应。儿童肥胖是一个重大的公共卫生问题，尤其是在有儿科残疾的人群中。这项研究将研究一种新的机制来解释唐氏综合症青少年中肥胖率更高的原因。通过在日常生活中和在可改变的健康行为的背景下研究这一机制，这项拟议的研究可能会促进未来有效干预和预防计划的发展。这一F31博士前奖学金旨在扩大我目前的博士生培训和研究潜力。主要目标将是获得研究技能，使我能够研究导致唐氏综合症青少年健康差距和肥胖的神经内分泌和生理因素。该奖项将提供：1)更多的时间专注于拟议的研究项目；以及2)额外的资源，以增加我在高级运动生理学、代谢内分泌学和肥胖症病理生理学方面的研究培训。这项全面的培训计划和拟议的研究项目将研究一种新的机制，可以更好地解释这一“高危”人群的肥胖问题。培训将为我提供一系列研究工具，以研究儿科残疾人群中的肥胖问题，并开发创新的未来干预措施，在我的职业生涯中减少儿科肥胖症。

DESCRIPTION (provided by applicant): The prevalence of overweight and obesity among adolescents with Down syndrome exceeds 50% and is significantly greater than rates observed in the general population. This condition persists into adulthood and contributes to the development of additional secondary health conditions. Thus, obesity represents a predominant source of health disparity. It remains unclear what causes the higher prevalence of obesity among adolescents with Down syndrome. Glucocorticoid (i.e. cortisol) function may be a novel neuroendocrine mechanism to explain the increased risk of obesity in this population. Recent research suggests that young adults with Down syndrome exhibit cortisol dysregulation compared to adults without disabilities. Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and cortisol function have been shown to promote weight gain and greater abdominal fat mass in the general population. However, it remains unclear whether differences in cortisol functioning in adolescents with Down syndrome contribute to the greater prevalence of obesity. Furthermore, many interventions to address pediatric obesity involve exercise. Normal cortisol response to exercise is expected to have a protective effect on obesity development, but it is unclear how cortisol response to exercise is associated with obesity in adolescents with Down syndrome. This fellowship application, therefore proposes to study how cortisol function mediates the association between fat mass (obesity) and Down syndrome under two conditions: 1) daily living in the natural environment; and 2) in response to a bout of moderate-intensity exercise. Pediatric obesity is significant public health problem, especially in populations with pediatric disabilities. This research will examine a novel mechanism to explain the greater obesity prevalence among youth with Down syndrome. Through studying this mechanism during daily life and in the context of a modifiable health behavior, this proposed study may promote the development of effective interventions and prevention programs in the future. This F31 Pre-doctoral Fellowship seeks to expand my current doctoral training and research potential. The primary goal will be to gain research skills that will enable me to study neuroendocrine and physiological factors that contribute to health disparities and obesity among youth with Down syndrome. The award will provide: 1) more time to focus on the proposed research project; and 2) additional resources to increase my research training in advanced exercise physiology, metabolic endocrinology and the pathophysiology of obesity. The comprehensive training plan and proposed research project will examine a novel mechanism that could better explain obesity in this "at-risk" population. Training will provide me with a rane of research tools to study obesity in populations with pediatric disabilities and develop innovative future interventions to reduce pediatric obesity throughout my career.