Song Yu, Xu Wenwen, Chen Shanshan, Hu Guanjie, Ge Honglin, Xue Chen, Qi Wenzhang, Lin Xingjian, Chen Jiu
Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China.
Institute of Neuropsychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China.
Front Aging Neurosci. 2021 Jul 26;13:695210. doi: 10.3389/fnagi.2021.695210. eCollection 2021.
Mild cognitive impairment (MCI) is an intermediate stage between normal aging and dementia. Amnestic MCI (aMCI) and non-amnestic MCI are the two subtypes of MCI with the former having a higher risk for progressing to Alzheimer's disease (AD). Compared with healthy elderly adults, individuals with MCI have specific functional alterations in the salience network (SN). However, no consistent results are documenting these changes. This meta-analysis aimed to investigate the specific functional alterations in the SN in MCI and aMCI. We systematically searched PubMed, Embase, and Web of Science for scientific neuroimaging literature based on three research methods, namely, functional connectivity (FC), regional homogeneity (ReHo), and the amplitude of low-frequency fluctuation or fractional amplitude of low-frequency fluctuation (ALFF/fALFF). Then, we conducted the coordinate-based meta-analysis by using the activation likelihood estimation algorithm. In total, 30 functional neuroimaging studies were included. After extracting the data and analyzing it, we obtained specific changes in some brain regions in the SN including decreased ALFF/fALFF in the left superior temporal gyrus, the insula, the precentral gyrus, and the precuneus in MCI and aMCI; increased FC in the thalamus, the caudate, the superior temporal gyrus, the insula, and the cingulate gyrus in MCI; and decreased ReHo in the anterior cingulate gyrus in aMCI. In addition, as to FC, interactions of the SN with other networks including the default mode network and the executive control network were also observed mainly in the middle frontal gyrus and superior frontal gyrus in MCI and inferior frontal gyrus in aMCI. Specific functional alternations in the SN and interactions of the SN with other networks in MCI could be useful as potential imaging biomarkers for MCI or aMCI. Meanwhile, it provided a new insight in predicting the progression of health to MCI or aMCI and novel targets for proper intervention to delay the progression. [PROSPERO], identifier [No. CRD42020216259].
轻度认知障碍(MCI)是正常衰老与痴呆之间的中间阶段。遗忘型MCI(aMCI)和非遗忘型MCI是MCI的两种亚型,前者发展为阿尔茨海默病(AD)的风险更高。与健康老年人相比,MCI患者在突显网络(SN)中存在特定的功能改变。然而,尚无一致的结果记录这些变化。本荟萃分析旨在研究MCI和aMCI患者SN中的特定功能改变。我们基于三种研究方法,即功能连接(FC)、局部一致性(ReHo)以及低频振幅或低频振幅分数(ALFF/fALFF),系统检索了PubMed、Embase和Web of Science上的科学神经影像学文献。然后,我们使用激活似然估计算法进行基于坐标的荟萃分析。总共纳入了30项功能性神经影像学研究。在提取数据并进行分析后,我们获得了SN中一些脑区的特定变化,包括MCI和aMCI患者左侧颞上回、岛叶、中央前回和楔前叶的ALFF/fALFF降低;MCI患者丘脑、尾状核、颞上回、岛叶和扣带回的FC增加;aMCI患者前扣带回的ReHo降低。此外,关于FC,还观察到SN与其他网络(包括默认模式网络和执行控制网络)的相互作用,主要见于MCI患者的额中回和额上回以及aMCI患者的额下回。SN中的特定功能改变以及MCI中SN与其他网络的相互作用可能作为MCI或aMCI潜在的影像学生物标志物。同时,它为预测健康向MCI或aMCI的进展提供了新的见解,并为适当干预以延缓进展提供了新的靶点。[国际前瞻性系统评价注册库(PROSPERO)],标识符[编号CRD42020216259]