Neuroendocrine Factors in Adolescent Obesity

描述(由申请者提供)：肥胖是一种流行病，比以往任何时候都更年轻。肥胖与包括生长激素、生长激素(GH)和胰岛素在内的几种激素的分泌模式的变化有关，这些激素在青少年年龄组中尚未被检测到。Ghrelin主要是一种胃激素，可以增加食欲，是一种生长激素促分泌剂。本研究通过频繁采血、生长激素释放激素和精氨酸刺激试验，比较超重和正常体重青春期女孩生长激素和生长激素分泌的变化。我们将研究这些激素与胰岛素抵抗之间的关系，通过1H-核磁共振波谱测量，以及通过双能X射线吸收测量仪和磁共振成像测量身体成分。这项研究还将确定餐后Ghrelin对不同类型的主要常量营养素的不同测试用餐的反应，这可能预测饥饿的程度和下一顿饭的摄入量。了解与肥胖相关的Ghrelin和GH的变化及其与身体成分、胰岛素抵抗和食欲的关系将有助于制定减少肥胖并发症的策略。

DESCRIPTION (provided by applicant): Obesity is an epidemic that is striking people at younger ages than ever before. Obesity is associated with changes in the secretory patterns of several hormones including ghrelin, growth hormone (GH), and insulin, which have not been examined in the adolescent age group. Ghrelin, a primarily gastric hormone, increases appetite and is a GH secretagogue. This study will compare the alteration in secretion of ghrelin and GH in overweight and normal weight adolescent girls through frequent blood sampling and GH stimulation testing with growth hormone releasing hormone and arginine. The relationship between these hormones and insulin resistance, measured by 1H-nuclear magnetic resonance spectroscopy, and body composition, measured by dual energy x-ray absorptiometry and magnetic resonance imaging, will be investigated. This study will also determine the postprandial ghrelin response to test meals that vary by the type of predominant macronutrient, which may predict the degree of hunger and amount of intake at a subsequent meal. Understanding obesity-related changes in ghrelin and GH and their relationship to body composition, insulin resistance, and appetite will help in the development of strategies to reduce complications of obesity.