Dawn Phenomena: Lowering Impaired Fasting Glucose Levels with Exercise (LIFE)

 描述（由申请人提供）：早晨高血糖在胰岛素抵抗和2型糖尿病（T2 D）的未来发展中起作用，并与许多微血管和心血管并发症以及肾脏疾病相关。这些增加的早晨葡萄糖水平是由于升高的内源性葡萄糖产生（EGP），这是由于葡萄糖水平和胰岛素分泌之间的协调丧失以及可能的过夜期间的高胰高血糖素血症。运动刺激葡萄糖摄取，并迅速增加胰岛素敏感性，可能是最好的生活方式干预，以尽量减少夜间葡萄糖水平的上升。对于空腹血糖（IFG）水平受损的个体，相对于进餐和/或过夜时间的运动时间的处方可能特别重要。令人惊讶的是，我们对EGP升高以及葡萄糖和C-肽/胰高血糖素水平之间的同步性受到干扰的过夜时间知之甚少。这项新研究将深入了解非肥胖、OB和OB+IFG个体晚餐、晚间和夜间的激素/代谢环境;它还将确定运动时间是否可以减轻夜间血糖升高，以及这是否与改善激素同步性相关。该项目将比较有/无IFG水平的肥胖个体在餐后和夜间晨练之间的EGP、β细胞功能和激素反应。将在晚餐期间（EGP和β细胞功能）、餐后和整个过夜期间（1600-0700 h）研究54例受试者，使我们能够检查过夜葡萄糖水平升高的一些潜在机制。这是第一项研究，将探讨这个问题，从晚餐前到晚上，而以前的研究只研究了长期禁食的人，这项研究将奠定基础，了解病理学的黎明前现象在OB+IFG个人。这些潜在的翻译结果可能会影响医生与患者就运动进行沟通的效率。我们是为数不多的几个研究对象通过过夜期间，并有设施和能力做这项研究的团体之一。

 DESCRIPTION (provided by applicant): Morning hyperglycemia plays a role in the future development of insulin resistance and type 2 diabetes (T2D) and is associated with numerous microvascular and cardiovascular complications and renal disease. These augmented morning glucose levels are due to an elevated endogenous glucose production (EGP), as a result of a loss of coordination between glucose levels and insulin secretion, and possibly hyperglucagonemia during the overnight period. Exercise stimulates glucose uptake and increases insulin sensitivity acutely, and may be the best lifestyle intervention to minimize the nocturnal rise in glucose levels. Prescription of the timing of exercise relative to a meal and/or o the overnight period may be particularly critical for individuals that have impaired fasting glucos (IFG) levels. Surprisingly we know little about the overnight period when elevated EGP and the synchrony between glucose and c-peptide/glucagon levels becomes disturbed. This novel study will provide insight into the hormonal/metabolic milieu of a dinner meal, the evening and overnight period that occurs in non-obese, OB and OB+IFG individuals; it will also establish if the timing of exercise can attenuate nocturnal glucose elevations, and if this is associated with improved hormonal synchrony. This project will compare EGP, β-cell function and hormonal responses between morning and evening exercise on the postprandial and overnight period in obese individuals with/without IFG levels. Fifty-four subjects will be studied during the evening meal (EGP and β-cell function), postprandially and through the overnight period (1600-0700 h), allowing us to examine some of the potential mechanisms for the elevation in overnight glucose levels. This is the first study that will examine this issue from pre-dinner through the night whil previous studies have only examined chronically fasted individuals and this study will lay the groundwork for understanding the pathology of the predawn phenomena in OB+IFG individuals. These potentially translational findings may impact the efficiency of physician communication to patients concerning exercise. We are one of the few groups that study subjects through the overnight period and have the facilities and capability to do this research.