HORMONAL AND METABOLIC IMPACT OF BINGE EATING IN WOMEN

本研究的总体目的是确定等热量暴饮暴食对胰岛素水平的影响程度;确定胰岛素对暴饮暴食的反应机制，饮食诱导的胰岛素变化对生殖功能的影响，以及胰岛素和雄激素对血脂变化的相对影响。饮食失调的行为，特别是暴饮暴食，在肥胖的老年人和非肥胖的年轻美国妇女中都令人惊讶地普遍存在。 许多心血管疾病的危险因素，包括肥胖、体脂肪的腹部沉积、高胰岛素血症、糖尿病、高脂血症和高血压，可以受到饮食行为的环境影响的强烈影响。 进食的时间模式对胰岛素代谢有显著影响，因为更频繁的小餐会迅速导致平均胰岛素水平低于一日三餐。 虽然高胰岛素血症通常与高脂血症有关，但来自饮食模式的其他代谢信号也可能影响脂质水平。 例如，雄激素与LDL胆固醇水平升高呈正相关，饮食似乎能够通过增加或减少促性腺激素水平来影响雄激素水平。 进食行为、胰岛素水平、促性腺激素水平和卵巢雄激素分泌之间的关系对于理解多囊卵巢综合征（PCOS）的病理生理学至关重要，其中受影响的妇女是月经过少和高雄激素的，以及高胰岛素血症。 与正常女性相比，其他女性是高胰岛素血症，包括肥胖女性和糖尿病前期女性，但其与PCOS女性的相似性和差异性尚未得到很好的描述。 到目前为止，在这些诊断子集中仅发现了少数原发性遗传缺陷，因此胰岛素抵抗的功能缺陷在肥胖，糖尿病前期和PCOS女性中表现相似。 这些研究旨在实现三个主要目标：1）确定进食行为对PCOS表型表达的贡献，2）使用暴饮暴食诱导的高胰岛素血症作为实验模型来评估胰岛素对促性腺激素动力学、卵巢雄激素反应性和随后的脂质水平的影响，和3）与单纯肥胖或因糖尿病前期而高胰岛素血症的妇女相比，确定PCOS妇女独特的病理生理机制。

The overall aim of this study is to determine the degree to which isocaloric binge eating effects insulin levels; identify the mechanisms of the insulin response to binge eating, the impact of eating-induced changes in insulin on reproductive function, and the relative impact of insulin and androgen changes of lipid profile. Disordered eating behaviors, especially binge eating, are surprisingly prevalent in both obese older individuals and in non-obese young American women. Many of the risk factors for cardiovascular disease, including obesity, abdominal deposition of body fat, hyperinsulinemia, diabetes, hyperlipidemia, and hypertension, can be strongly influenced by the environment impact of eating behavior. The temporal pattern of eating has a significant impact on insulin metabolism in that more frequent small meals rapidly result inlower mean insulin levels than even three meals per day. Although hyperinsulinemia is typically associated with hyperlipidemia, other metabolic signals from the eating pattern may also influence lipid levels. For example, androgens are positively associated with elevated LDL cholesterol levels, and diet appears able to influence androgen levels by increasing or decreasing gonadotropin levels. The relationships between eating behavior, insulin levels, gonadotropin levels, and ovarian androgen secretion are critical to understanding the pathophysiology of Polycystic Ovary Syndrome (PCOS), in which affected women are oligomenorrheic and hyperandrogenic, as well as hyperinsulinemic. Other women are hyperinsulinemic compared to normal women, including obese women and pre-diabetic women, but their similarities and differences with women with PCOS have not been well delineated. To date, a primary genetic defect has been discerned in only a minority of these diagnostic subsets, so that functional defects of insulin resistance appear similar in obese, pre-diabetic, and PCOS women. These studies are designed for three major goals: 1) to determine the contribution of eating behavior to the expression of the PCOS phenotype, 2) to use binge eating-induced hyperinsulinemia as a experimental model to assess the effects of insulin on gonadotropin dynamics, ovarian androgen responsiveness, and subsequent lipid levels, and 3) to identify unique pathophysiologic mechanisms in women with PCOS compared to women who are simply obese or who are hyperinsulinemic because they are pre-diabetic.