Abstract：
Positron emission tomography (PET) and magnetic resonance spectroscopy (1H-MRS) are complementary techniques that can be applied to study how proteinopathy and neurometabolism relate to cognitive deficits in preclinical stages of Alzheimer\'s disease (AD)-mild cognitive impairment (MCI) and late-life depression (LLD). We acquired beta-amyloid (Aβ) PET and 7 T 1H-MRS measures of GABA, glutamate, glutathione, N-acetylaspartate, N-acetylaspartylglutamate, myo-inositol, choline, and lactate in the anterior and posterior cingulate cortices (ACC, PCC) in 13 MCI and 9 LLD patients, and 13 controls. We used linear regression to examine associations between metabolites, Aβ, and cognitive scores, and whether metabolites and Aβ explained cognitive scores better than Aβ alone. In the ACC, higher Aβ was associated with lower GABA in controls but not MCI or LLD patients, but results depended upon MRS data quality control criteria. Greater variance in California Verbal Learning Test scores was better explained by a model that combined ACC glutamate and Aβ deposition than by models that only included one of these variables. These findings identify preliminary associations between Aβ, neurometabolites, and cognition.
摘要：
正电子发射断层扫描（PET）和磁共振波谱（1H-MRS）是补充技术，可用于研究阿尔茨海默病（AD）-轻度认知障碍（MCI）的临床前阶段蛋白质病和神经代谢与认知障碍的关系。晚期抑郁症（LLD）。我们获得了GABA的β-淀粉样蛋白（Aβ）PET和7T1H-MRS测量值，谷氨酸,谷胱甘肽,N-乙酰天冬氨酸,N-乙酰天冬氨酰谷氨酸,肌醇,胆碱，和前扣带回皮质和后扣带回皮质中的乳酸(ACC，PCC)在13名MCI和9名LLD患者中，13个控件我们使用线性回归来检查代谢物之间的关联，Aβ,和认知分数，以及代谢物和Aβ是否比单独的Aβ更好地解释了认知评分。在ACC中,在对照组中，较高的Aβ与较低的GABA相关，但与MCI或LLD患者无关，但结果取决于MRS数据质量控制标准。结合ACC谷氨酸和Aβ沉积的模型比仅包含这些变量之一的模型更好地解释了加利福尼亚言语学习测试得分更大的差异。这些发现确定了Aβ之间的初步关联，神经代谢物，和认知。
