fMRI and Ghrelin in Obesity and Binge Eating Disorder

描述（由申请人提供）：美国和全球肥胖症的患病率持续增加。肥胖导致发病率和死亡率增加，特别是糖尿病和心脏病。大约30%寻求治疗的肥胖个体患有暴食症（BED）。他们吃下大量的食物，但之后没有像神经性贪食症那样进行净化。BED是最常见的特征性饮食失调，引起许多痛苦并有助于肥胖的发展。虽然心理因素已被研究，但对BED的生物因素知之甚少。这项临床研究将重点关注餐后大脑成像和肠道激素，以检查BED和非BED受试者之间的差异。将有24例肥胖BED（12个月，12个月）和24例体重匹配的肥胖非BED（12个月，12个月）受试者。在一天，将摄入固定的液体餐（750 ml），并抽血以测量各种食欲激素，包括胃饥饿素、PYY和GLP-1，在之前和之后2小时内测量。与非BED受试者相比，BED受试者的空腹ghrelin水平较低，餐后下降幅度较小。与非BED受试者相比，BED受试者的PYY和GLP-1空腹水平较低，餐后增加较小。另一天，仅摄入水（750 ml）作为这些激素昼夜变化的对照。在固定餐或水后135分钟，将采用功能成像（fMRI）检查大脑激活区域对暴饮暴食、非暴饮暴食和非食物的视觉和听觉刺激的反应。与非卧床受试者相比，卧床受试者对暴饮暴食的反应相对于其他刺激组而言，预期前额叶皮层等区域的激活程度更高。在BED受试者中，即使在进食状态下，预期激活增加也会导致暴饮暴食，因为暴饮暴食通常发生在不存在饥饿的情况下。在第三天，将管理各种心理量表以评估饮食行为和情绪。将测量身体组成以获得体脂百分比，以验证两组中相似的身体组成。这项关于大脑成像和与膳食相关的食欲激素的研究应该提高我们对暴食症（BED）潜在生物因素的认识。这可能会导致改善诊断和治疗，以帮助恢复正常的食欲激素水平和大脑活动在床，这是一种疾病，这是增加流行与肥胖。

DESCRIPTION (provided by applicant): The prevalence of obesity continues to increase in the US and globally. Obesity results in increased morbidity and mortality, especially from diabetes and heart disease. Approximately 30% of obese individuals seeking treatment have binge eating disorder (BED). They ingest very large meals without purging afterwards as in bulimia nervosa. BED, the most common characterized eating disorder, causes much distress and contributes to the development of obesity. Although psychological factors have been studied, little is known about the biological factors of BED. This clinical research study will focus on brain imaging and gut hormones following a meal to examine differences between BED and non-BED subjects. There will be 24 obese BED (12 m, 12 f) and 24 weight-matched obese non-BED (12 m, 12 f) subjects. On one day, a fixed liquid meal (750 ml) will be ingested and blood drawn to measure various appetite hormones including ghrelin, PYY, and GLP-1, measured before and during a 2-hour period afterwards. The prediction is a lower fasting level of ghrelin and a smaller postprandial fall in BED compared to non-BED subjects. Also predicted are lower fasting levels and smaller postprandial increases of PYY and GLP-1 in BED compared to non-BED subjects. On another day, only water (750 ml) will be ingested as a control for diurnal variation in these hormones. At 135 min after the fixed meal or water, functional imaging (fMRI) will be employed to examine brain activation areas in response to visual and auditory stimuli of binge foods, nonbinge foods, and nonfoods. Greater activation is expected in such areas as the prefrontal cortex in response to binge foods relative to the other stimuli groups in BED than in nonBED subjects. Increased activation is also expected to binge food stimuli in the BED subjects even in the fed state as binge eating often occurs in the absence of hunger. On a third day, various psychological scales to assess eating behavior and mood will be administered. Body composition will be measured to obtain percentage body fat to verify similar body composition in the two groups. This study on brain imaging and meal-related appetite hormones should improve our knowledge of the underlying biological factors in Binge Eating Disorder (BED). This may lead to improved diagnosis and treatments to help restore normal appetite hormone levels and brain activity in BED, a disorder which is increasing in prevalence alongside obesity.