LEGUME FEEDING STUDY

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。高豆类、低血糖指数饮食的有益作用的工作假设是，食物中的膳食纤维含量可能降低碳水化合物的吸收速率，降低餐后血糖和胰岛素血症反应，导致C肽和其他胰岛素抵抗标志物的水平降低。豆类中高水平的可发酵纤维将被结肠细菌降解为短链脂肪酸，包括丁酸盐，一种具有抗炎和抗肿瘤特性的分子。胰岛素的降低和丁酸盐的增加都将降低CRP和其他炎症生物标志物，并将改变粪便结肠细胞中炎症和胰岛素相关基因的表达水平。另一个正在研究的假设是，高豆类，高纤维饮食将导致胆囊收缩素（CCK），生长激素释放肽和瘦素的循环水平的变化，这将增加饱腹感和减轻体重。 研究目的：这是一项随机交叉对照喂养研究，其中每位参与者将食用高豆类，低血糖指数饮食四周，对照美国饮食四周，饮食之间休息三周。这两个饮食阶段将是体重稳定的。额外的饮食期将是可选的，他们将消耗相同的富含豆类的饮食，但体重减轻将是允许的。这项研究将有四组男性参与者：1。腺瘤和IR既往史; 2.腺瘤既往史，无IR; 3.无腺瘤病史的IR;和4.无IR和腺瘤病史。主要目的是评估饮食对这一人群中两个终点（C反应蛋白和C肽）的总体影响。次要目的是评估这些干预相关终点的变化是否因IR状态或腺瘤病史而异。此外，将测量粪便钙卫蛋白和结肠细胞RNA，以评估胃肠道炎症的变化。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The working hypothesis for the beneficial effects of a high legume, low glycemic index diet is that the dietary fiber content of the food may reduce the rate of the absorption of the carbohydrates and lower the postprandial glycemic and insulinemic responses leading to a reduced level of C-peptide and other markers of insulin resistance. The high level of fermentable fibers in legumes will be degraded by colonic bacteria to short chain fatty acids, including butyrate, a molecule with demonstrated anti-inflammatory and anti-neoplastic properties. The lowering of insulin and the increase in butyrate will both lower CRP, and other biomarkers of inflammation, and will alter expression level of inflammatory and insulin related genes in fecal colonocytes. An additional hypothesis being investigated is that a high legume, high fiber diet will result in changes in circulating levels of cholecystokin (CCK), ghrelin, and leptin which will increase satiety and reduce body weight. Study Objectives: This is a randomized crossover controlled feeding study in which each participant will consume a high legume, low glycemic index diet for four weeks and a control American diet for four weeks, with a three week break between diets. These two diet periods will be weight stable. An additional diet period will be optional in which they will consume the same legume rich diet, but weight loss will be permitted. The study will have four groups of male participants: 1. previous history of adenomas and IR; 2. previous history of adenomas and not IR; 3. IR with no history of adenomas; and 4. non-IR and no history of adenomas. The primary objective is to assess an overall effect of diet on the two endpoints, C-reactive protein and C-peptide in this population. A secondary objective is to assess whether changes in these intervention-related endpoints will differ by IR status or a history of adenomas. In addition, fecal calprotectin and colonocyte RNA will be measured to assess changes in gastrointestinal inflammation.