DIETARY RESTRICTION METABOLIC ALTERATIONS IN SARCOPENIA

随着年龄的增长，骨骼肌量的减少(骨质疏松症)对公众健康很重要，因为它影响到 老年人的功能能力。恒河猴为研究石棺减少症和 饮食限制(DR)对灵长类动物进展的影响。我们假设DR引起一种改变的状态 线粒体能量代谢是延缓衰老的关键因素，这种“代谢变化” 负责减缓DR动物的石棺减少的速度。 具体目标1：建立年龄和DR对骨骼的影响的转录和蛋白质组学图谱 肌肉。这是一项对1994年1组猕猴股外侧肌(VL)活检的纵向研究。 研究的第一年。Affymetrix人类微阵列数据将被挖掘以探测中心基因的功能群 能量代谢，重点是与线粒体功能有关的基因。比较蛋白质组学分析 来自相同活检组织和第二组动物的线粒体，使用2D电泳法和质谱仪，将 进一步定义线粒体的状态。Western印迹分析将确认微阵列工作的结果和 研究年龄和DR对参与代谢调节和细胞信号转导的特定蛋白质的影响。 具体目标2：确定恒河猴出现石腐症表型的临界年龄 并确定DR在肌肉随年龄变化过程中的作用。对中国经济变化的分析 威斯康星州国家灵长类研究中心(WNPRC)群体和PPG支持的男性和女性股四头肌 在尸检中收集的猴子，以及来自对照猴子和DR猴子的活检样本，结合 随着时间的推移，对活猴子的纵向DXA和MRI肌肉质量的估计将定义特定的年龄 衰老过程中出现的肌肉质量下降、肌纤维丢失、肌纤维萎缩和线粒体酶异常 恒河猴。 具体目标3：定量检测单个个体mtDNA缺失突变和特定mRNAs的丰度 肌肉纤维的显微解剖切片。激光捕获显微解剖将用于从DR和 对照组猕猴股外侧肌单一肌纤维表现为ETS正常和ETS异常表型。这个 Wt和mtDNA缺失突变的丰度以及选定的mRNAs的水平，其丰度 随着年龄和/或饮食的变化(在目标1中确定)，将被量化。

The loss of skeletal muscle mass with aging (sarcopenia) is important to public health due to its effects on the functional capacity of older adults. The rhesus monkey provides an outstanding model to study sarcopenia and the effect of dietary restriction (DR) on its progression in primates. We hypothesize that DR induces an altered state of mitochondrial energy metabolism that is central to the retardation of aging, and that this "metabolic shift" is responsible for slowing the rate of sarcopenia in DR animals. Specific Aim 1: To generate transcriptional and proteomic profiles of the effects of age and DR on skeletal muscle. This is a longitudinal study on vastus lateralis (VL) biopsies obtained from Group 1 monkeys in 1994 and year one of the study. Affymetrix human microarray data will be mined to probe functional groups of genes central to energy metabolism with a focus on genes involved in mitochondrial function. Comparative proteomic analysis of mitochondria from the same biopsies and Group 2 animals, using 2D electrophoresis and mass spectrometry, will further define mitochondrial status. Western blot analysis will confirm the results of the microarray work and examine the effect of age and DR on specific proteins involved in metabolic regulation and cell signaling. Specific Aim 2: To identify critical ages at which phenotypes of sarcopenia emerge in the rhesus monkey and to define the effect of DR on the progression of muscle changes with age. Analyses of changes in quadriceps muscles from male and female Wisconsin National Primate Research Center (WNPRC) colony and PPGsupported monkeys collected at necropsy, as well as biopsy samples from control and DR monkeys, combined with longitudinal DXA and MRI muscle mass estimations from live monkeys over time, will define specific ages at which muscle mass loss, muscle fiber loss, muscle fiber atrophy and mitochondrial enzyme abnormalities present in aging rhesus monkeys. Specific Aim 3: To quantitate mtDNA deletion mutations and abundance of specific mRNAs in single microdissected sections of muscle fibers. Laser capture microdissection will be used to select, from DR and control monkeys, single vastus lateralis muscle fibers exhibiting ETS normal and ETS abnormal phenotypes. The abundance of WT and mtDNA deletion mutations as well as the levels of selected mRNAs, the abundance of which change with age and/or diet (identified in Aim 1), will be quantified.