Moeller J R, Ishikawa T, Dhawan V, Spetsieris P, Mandel F, Alexander G E, Grady C, Pietrini P, Eidelberg D
Department of Psychiatry, New York State Psychiatric Institute, Columbia College of Physicians and Surgeons, New York, USA.
J Cereb Blood Flow Metab. 1996 May;16(3):385-98. doi: 10.1097/00004647-199605000-00005.
Normal aging is associated with the degeneration of specific neural systems. We used [18F] fluorodeoxyglucose (FDG)/positron emission tomography (PET) and a statistical model of regional covariation to explore the metabolic topography of this process. We calculated global and regional metabolic rates for glucose (GMR and rCMRglc) in two groups of normal subjects studied independently on different tomographs: Group 1--130 normal subjects (62 men and 68 women; range 21-90 years); Group 2--20 normal subjects (10 men and 10 women; range 24-78 years). In each of the two groups, the Scaled Subprofile Model (SSM) was applied to rCMRglc data to identify specific age-related profiles. The validity of these profiles as aging markers was assessed by correlating the associated subject scores with chronological age in both normal populations. SSM analysis disclosed two significant topographic profiles associated with aging. The first topographic profile, extracted in an analysis of group 1 normals, was characterized by relative frontal hypometabolism associated with covariate metabolic increases in the parietooccipital association areas, basal ganglia, mid-brain, and cerebellum. Subject scores for this profile correlated significantly with age in both normal groups (R2 = 0.48 and 0.33, p < 0.0001 for groups 1 and 2, respectively). Because of clinical similarities between normal motoric aging and parkinsonism, we explored the possibility of shared elements in the metabolic topography of both processes. We performed a combined group SSM analysis of the 20 group 2 normals and 22 age-matched Parkinson's disease patients, and identified another aging-related topographic profile. This profile was characterized by relative basal ganglia hypermetabolism associated with covariate decreases in frontal premotor cortex. Subject scores for this profile also correlated significantly with age in both normal groups (group 1: R2 = 0.30, p < 0.00001; group 2: R2 = 0.59, p < 0.01). Healthy aging is associated with reproducible topographic covariation profiles associated with specific neural systems. FDG/PET may provide a useful metabolic marker of the normal aging process.
正常衰老与特定神经系统的退化有关。我们使用[18F]氟脱氧葡萄糖（FDG）/正电子发射断层扫描（PET）以及区域协变统计模型来探究这一过程的代谢地形图。我们在两组分别在不同断层扫描仪上独立研究的正常受试者中计算了葡萄糖的整体和区域代谢率（GMR和rCMRglc）：第1组——130名正常受试者（62名男性和68名女性；年龄范围21 - 90岁）；第2组——20名正常受试者（10名男性和10名女性；年龄范围24 - 78岁）。在两组中的每一组，将缩放子剖面模型（SSM）应用于rCMRglc数据，以识别特定的年龄相关剖面。通过将相关受试者分数与两个正常人群的实际年龄进行关联，评估这些剖面作为衰老标志物的有效性。SSM分析揭示了两个与衰老相关的显著地形图剖面。在对第1组正常受试者的分析中提取的第一个地形图剖面，其特征是额叶相对代谢减退，同时顶枕联合区、基底神经节、中脑和小脑的协变量代谢增加。该剖面的受试者分数在两个正常组中均与年龄显著相关（第1组和第2组的R2分别为0.48和0.33，p均<0.0001）。由于正常运动衰老与帕金森病在临床上存在相似性，我们探究了这两个过程的代谢地形图中是否存在共同元素。我们对20名第2组正常受试者和22名年龄匹配的帕金森病患者进行了联合组SSM分析，并确定了另一个与衰老相关的地形图剖面。该剖面的特征是基底神经节相对代谢亢进，同时额叶运动前区皮质的协变量减少。该剖面的受试者分数在两个正常组中也与年龄显著相关（第1组：R2 = 0.30，p < 0.00001；第2组：R2 = 0.59，p < 0.01）。健康衰老与特定神经系统相关的可重复地形图协变剖面有关。FDG/PET可能为正常衰老过程提供一个有用的代谢标志物。
