Liu Qing, Zhu Zude, Teipel Stefan J, Yang Jianwei, Xing Yi, Tang Yi, Jia Jianping
Department of Neurology, Xuan Wu Hospital, Capital Medical University Beijing, China.
Collaborative Innovation Center for Language Competence, Jiangsu Normal University Xuzhou, China.
Front Aging Neurosci. 2017 Feb 27;9:47. doi: 10.3389/fnagi.2017.00047. eCollection 2017.
Cholinergic deficiency has been implicated in the pathogenesis of vascular cognitive impairment (VCI), but the extent of involvement and underlying mechanism remain unclear. In this study, targeting the early stage of VCI, we determined regional atrophy within the basal forebrain and deficiency in cholinergic pathways in 25 patients with vascular cognitive impairment no dementia (VCIND) compared to 24 healthy elderly subjects. By applying stereotaxic cytoarchitectonic maps of the nucleus basalis of Meynert (NbM), no significant atrophy was identified in VCIND. Using probabilistic tractography analysis, our study tracked the two major white matter tracks which map to cholinergic pathways. We identified significantly lower fractional anisotropy (FA) in VCIND. Mediation analysis demonstrated that FA in the tracked pathways could fully account for the executive dysfunction, and partly mediate the memory and global cognition impairment. Our study suggests that the fibers mapped to the cholinergic pathways, but not the NbM, are significantly impaired in VCIND. MRI-based tracking of cholinergic pathways together with NbM measurement may become a valuable marker for evaluating the cholinergic system in cognitive disorders.
胆碱能缺乏已被认为与血管性认知障碍（VCI）的发病机制有关，但受累程度及潜在机制仍不清楚。在本研究中，针对VCI的早期阶段，我们确定了25例无痴呆的血管性认知障碍（VCIND）患者与24例健康老年受试者相比，基底前脑的区域萎缩情况以及胆碱能通路的缺乏。通过应用迈内特基底核（NbM）的立体定向细胞构筑图谱，在VCIND患者中未发现明显萎缩。使用概率纤维束成像分析，我们的研究追踪了两条映射到胆碱能通路的主要白质束。我们发现VCIND患者的分数 anisotropy（FA）显著降低。中介分析表明，追踪通路中的FA可完全解释执行功能障碍，并部分介导记忆和整体认知障碍。我们的研究表明，映射到胆碱能通路的纤维而非NbM，在VCIND中显著受损。基于MRI的胆碱能通路追踪以及NbM测量可能成为评估认知障碍中胆碱能系统的有价值标志物。
