Gastrointestinal Hormonal Regulation of Obesity

描述(由申请人提供)： 项目摘要/摘要肥胖是退伍军人医疗系统中发病率和死亡率的主要原因，占糖尿病、高血压、冠状动脉疾病和脑血管意外的大部分。更好地了解我们的老年肥胖患者的体重调节将通过避免严重的医疗并发症和提出新的治疗方法来提高生活质量。本研究的目的是证实高蛋白饮食对肥胖患者减少食物摄入量和体重是有效、安全和有益的，并在相关实验模型上建立高蛋白饮食诱导早饱信号的神经激素机制，重点是激活胃迷走神经传入。我们将评估高蛋白饮食对肥胖患者的饱腹感和餐后胃肠激素模式的影响。一项为期24-30个月的随机对照研究将志愿者(年龄E30岁，体重指数27-40 kg/m2)分配到：1)极高蛋白饮食组，2)高蛋白饮食组，3)标准蛋白质饮食对照组，热量相同。所有受试者都将接受营养师的指导，并将进行循环肠道激素测定和生化分析。高蛋白饮食减少食物摄入量的神经体液机制将通过药理学和电生理学方法测试高蛋白释放的肠肽对肥胖大鼠迷走神经传入满足信号到大脑的增强作用来评估。此外，Fos免疫组织化学定位高蛋白饮食对脑神经元激活的反应，将使我们能够建立高蛋白饮食和标准蛋白饮食激活的不同回路。这些研究将为高蛋白饮食的减肥效果和餐后胃肠激素释放谱的相关变化提供临床基础，并在神经元(迷走神经传入)水平上揭示肥胖实验模型的潜在机制。拟议的研究将解决有关饱腹感/体重调节机制的重要病理生理学问题，并提供潜在的重要临床治疗策略。

DESCRIPTION (provided by applicant): Project Summary/Abstract Obesity is a major cause of morbidity and mortality within our VA medical system accounting for the majority of cases of diabetes mellitus, hypertension, coronary artery disease and cerebrovascular accidents. An improved understanding of the regulation of body weight in our veteran obese patients will improve the quality of life by avoidance of serious medical complications and by suggesting novel therapeutic approaches. The objective of this study is to establish that a high protein diet is efficacious, safe and beneficial to curtail food intake and body weight in obese patients and to establish the neurohormonal mechanisms of high protein diet-induced early satiety signal in relevant experimental model, focusing on activation of gastric vagal afferents. We will assess the efficacy of a high protein diet on satiety and pattern of postprandial gut hormone in obese patients. A randomized controlled study lasting 24-30 months will assign volunteer subjects (ages e30, BMI 27-40 kg/m2) to: 1) Very high protein diet group, 2) High protein diet group, and 3) Standard protein diet group as control with same calories. All the subjects will be followed by a dietitian and determination of circulating gut hormone and biochemical assays will be performed. Neurohumoral mechanisms through which high protein diet curtailed food intake will be assessed by testing the hypthesis of a potentiating effect of gut peptides released by high protein on vagal afferent satieting signaling to the brain in obese rats using pharmacologica and electrophysiologic approaches. In addition Fos immunohistochemistry to map brain neuronal activation in respone to high protein diet will allow us to establish differential circuitries activated by high vs standard protein diet. These studies will provide a clinical basis on the weight reducing effect of high protein diet and the associated alterations in the profile of postprandial gut hormones released, and unravel the underlying mechanisms at the neuronal (vagal afferent) level in an expermental model of obesity. The proposed studies will address important pathophysiological questions regarding the mechanisms regulating satiety/body weight as well as provide potentially important clinical treatment strategies.