HIGH-COMPLEX-HIGH-REFINED-CHO MEALS, AND LOW-CHO MEALS ON ENDOTHELIAL FUNCTION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 采用高分辨率超声对肱动脉进行血流介导的扩张术(FMD)是一种公认的无创生物测定方法，可用于检测人体内皮细胞产生的一氧化氮(NO)。NO被认为是一种有效的血管扩张剂，但在维持健康的内皮细胞和抑制动脉粥样硬化的发生、发展和临床表现的关键步骤方面，NO也具有相当大的作用。由于餐后状态可能在动脉粥样硬化的发展中至关重要，而且高谷物纤维的饮食与降低心血管疾病的风险有关，我们假设高碳水化合物、高纤维的膳食将显著改善FMD。相比之下，我们假设低碳水化合物的膳食会损害FMD，而高碳水化合物、低纤维的膳食对FMD没有影响。我们还假设，在低碳水化合物餐中添加高纤维早餐麦片可以减轻低碳水化合物餐后观察到的FMD损害。使用高分辨率超声和边缘检测软件对12名8-17岁超重或有超重风险的受试者、12名18-岁受试者和12名65岁及以上受试者在四顿早餐(高碳水化合物，高纤维；高碳水化合物，低纤维；低碳水化合物，低纤维；低碳水化合物，高纤维)每餐前、后2小时和4小时进行肱动脉血流介导的扩张(FMD)评估。将使用重复测量的方差分析来评估应对膳食挑战的口蹄疫密度的差异。

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. Flow-mediated dilation (FMD) of the brachial artery using high-resolution ultrasound is a well accepted non-invasive bioassay for in vivo endothelium-generated nitric oxide (NO) in humans. NO has been characterized as a potent vasodilator, but NO also has a considerable role in maintaining healthy endothelium and inhibiting key steps in the development, progression, and clinical manifestations of atherosclerosis. Because the postprandial state may be critical in the development of atherosclerosis, and because diets high in cereal fiber have been linked to reduced risk of cardiovascular disease, we hypothesize that a high-carbohydrate, high-fiber meal would acutely improve FMD. By contrast, we hypothesize that a low-carbohydrate meal will impair FMD, and that a high-carbohydrate, low-fiber meal will have no effect on FMD. We also hypothesize that the addition of a high-fiber breakfast cereal to the low-carbohydrate meal will attenuate the impairment of FMD observed after the low-carbohydrate meal. Brachial artery flow-mediated dilation (FMD) will be assessed before and at 2 h and 4 h after each of four breakfast meals (high-carbohydrate, high-fiber; high-carbohydrate, low-fiber; low-carbohydrate, low-fiber; low-carbohydrate, high-fiber) using high-resolution ultrasound and edge-detection software in 12 participants ages 8-17 who are overweight or at-risk for overweight, 12 participants ages 18-64, and 12 participants ages 65 and older. Analysis of variance with repeated measures will be used to assess differences in FMD in response to the meal challenges.