Valatkevičienė Kristina, Levin Oron, Šarkinaitė Milda, Vints Wouter A J, Kunickaitė Rimantė, Danylė Greta, Kušleikienė Simona, Sheoran Samrat, Česnaitienė Vida J, Masiulis Nerijus, Himmelreich Uwe, Gleiznienė Rymantė
Department of Radiology, Medical Academy, Lithuanian University of Health Sciences, LT-44307 Kaunas, Lithuania.
Department of Health Promotion and Rehabilitation, Lithuanian Sports University, LT-44221 Kaunas, Lithuania.
Diagnostics (Basel). 2023 Feb 9;13(4):654. doi: 10.3390/diagnostics13040654.
We implemented a multimodal approach to examine associations between structural and neurochemical changes that could signify neurodegenerative processes related to mild cognitive impairment (MCI). Fifty-nine older adults (60-85 years; 22 MCI) underwent whole-brain structural 3T MRI (T1W, T2W, DTI) and proton magnetic resonance spectroscopy (H-MRS). The regions of interest (ROIs) for H-MRS measurements were the dorsal posterior cingulate cortex, left hippocampal cortex, left medial temporal cortex, left primary sensorimotor cortex, and right dorsolateral prefrontal cortex. The findings revealed that subjects in the MCI group showed moderate to strong positive associations between the total N-acetylaspartate to total creatine and the total N-acetylaspartate to myo-inositol ratios in the hippocampus and dorsal posterior cingulate cortex and fractional anisotropy (FA) of WM tracts crossing these regions-specifically, the left temporal tapetum, right corona radiata, and right posterior cingulate gyri. In addition, negative associations between the myo-inositol to total creatine ratio and FA of the left temporal tapetum and right posterior cingulate gyri were observed. These observations suggest that the biochemical integrity of the hippocampus and cingulate cortex is associated with a microstructural organization of ipsilateral WM tracts originating in the hippocampus. Specifically, elevated myo-inositol might be an underlying mechanism for decreased connectivity between the hippocampus and the prefrontal/cingulate cortex in MCI.
我们采用了一种多模态方法来研究结构和神经化学变化之间的关联，这些变化可能表明与轻度认知障碍（MCI）相关的神经退行性过程。59名老年人（60 - 85岁；22名MCI患者）接受了全脑结构3T磁共振成像（T1加权、T2加权、扩散张量成像）和质子磁共振波谱（H - MRS）检查。H - MRS测量的感兴趣区域（ROI）包括背侧后扣带回皮质、左侧海马皮质、左侧内侧颞叶皮质、左侧初级感觉运动皮质和右侧背外侧前额叶皮质。研究结果显示，MCI组受试者海马体和背侧后扣带回皮质中总N - 乙酰天门冬氨酸与总肌酸的比值以及总N - 乙酰天门冬氨酸与肌醇的比值与穿过这些区域的白质束（特别是左侧颞叶毯部、右侧放射冠和右侧扣带回）的分数各向异性（FA）之间存在中度至强的正相关。此外，还观察到左侧颞叶毯部和右侧扣带回中肌醇与总肌酸的比值与FA之间存在负相关。这些观察结果表明，海马体和扣带回皮质的生化完整性与源自海马体的同侧白质束的微观结构组织有关。具体而言，肌醇升高可能是MCI中海马体与前额叶/扣带回皮质之间连接性降低的潜在机制。
