THE ROLE OF LEPTIN AND CYTOKINES IN BODY WEIGHT REGULATION OF OLDER ADULTS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。老年患者的体重减轻是一个普遍而令人担忧的问题。面对持续的减肥，食欲不振的原因尚不清楚。以前的研究表明，在非自愿减肥的老年人中，死亡率、虚弱和功能残疾都会增加。其他研究报告称，老年男性在卡路里限制后可能存在能量摄入的失调，以及瘦素稳态的异常。拟议项目的具体目的是确定一段时间的适度热量限制是否对健康的老年受试者的每日综合瘦素水平(AUC-Leptin)和静息能量消耗(REE)的抑制程度与年轻人相同，并确定在一段时间的饮食能量限制后，老年人的能量摄入补偿性增加是否与年轻人一样强劲。假设老年人在一段时间的卡路里限制后，由于瘦素或促炎细胞因子水平的不适当升高，无法增加能量摄入量和/或减少能量消耗。在为期八周的控制饮食干预期间，对健康的老年人和年轻人进行了横断面比较。在两周的减肥饮食之后，依次是两周的30%卡路里减少量和4周的临时食物摄入量。在每个饮食阶段后测量24小时血浆瘦素水平(AUC Leptin)、促炎细胞因子水平、身体成分的DEXA扫描和静息能量消耗(REE)。

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. Weight loss in geriatric patients is a common and worrisome problem. The etiology of lack of appetite in the face of continued weight loss is unknown. Previous studies have shown an increase in mortality rates, frailty, and functional disability among older persons with involuntary weight loss. Other studies have reported possible dysregulation of energy intake in older men after calorie restriction as well as abnormalities in leptin homeostasis. The specific aims of the proposed project are to determine whether a period of moderate caloric restriction suppresses integrated diurnal plasma leptin levels (AUC-leptin) and resting energy expenditure (REE) in healthy older subjects to the same degree as in young adults, and to determine whether the compensatory increase in energy intake following a period of dietary energy restriction is as robust in older subjects as it is in young adults. The hypothesis is that older adults are unable to increase their energy intake and/or decrease their energy expenditure after a period of calorie restriction due to inappropriately elevated levels of leptin or pro-inflammatory cytokines. A cross-sectional comparison of healthy older and younger adults during an eight-week controlled diet intervention was performed. Two weeks of a weight-maintaining diet were followed in sequence by 2 weeks of 30% caloric reduction and 4 weeks of ad libitum (ad lib) food intake. Integrated 24-hour plasma leptin levels (AUC leptin), pro-inflammatory cytokine levels, DEXA scan for body composition, and resting energy expenditure (REE) were measured after each diet phase.