Department of Neurology, Guihang Guiyang Hospital, Guiyang, Guizhou, China.
Department of Medical Imaging, Guizhou Provincial People's Hospital, Guiyang, Guizhou, China.
Neurol Sci. 2021 Nov;42(11):4707-4717. doi: 10.1007/s10072-021-05573-9. Epub 2021 Sep 16.
To explore the role of the central cholinergic system in amnestic mild cognitive impairment (aMCI) and mild vascular cognitive impairment (vMCI).
Twenty-five aMCI patients and 25 vMCI patients were enrolled in this study, and 25 healthy people were chosen as a control group. All participants performed a set of cognitive function scales and were subjected to a brain MRI. We analyzed differences in neuropsychological damage between groups, as well as the degree of brain atrophy and changes in the microstructure of central cholinergic pathways (CCP) in relation to effects on neuropsychological scores.
(1) Regarding neuropsychological characteristics of the three groups, scores on the MoCA scale, immediate memory, delayed recall, cued recall, long time prolonged recognition, and CDR-SB of the control group were significantly better than those of the aMCI and vMCI groups. Scores on immediate memory, delayed memory, cued recall, long time delayed recognition, and Forward of Digital Span Test (FDST) in the aMCI group were lower than those in the vMCI group. Compared with the aMCI group, the vMCI group was significantly delayed in Trail Making Test (TMA)-A, TMT-B, and TMT B-A. There were no significant differences in HAMA, HAMD, MMSE, MoCA, the Boston Naming Test (BNT), language fluency or visual scale of posterior atrophy (Koedam score) between the vMCI and aMCI groups. (2) As for microstructure changes in the central cholinergic pathway, vMCI group had a decreased FA value in the cingulum (Cing) of the medial pathway, but an increased MD value in the external capsule (Excap) of the lateral pathway when compared to other two groups. Furthermore, the CingMD value of the vMCI group was higher than that of the control group, but the difference was not obvious when compared to the aMCI group. (3) Last, we researched microstructural changes to CCP, degree of brain atrophy, and neuropsychological scores by using partial correlation analysis for all participants. CingFA was negatively correlated with TMT-B, B-A, and FDST. CingMD was negatively correlated with FDST. ExcapFA was positively correlated with MMSE and Backward of BDST, while ExcapMD was negatively correlated with MMSE and MoCA. Claustrum (Claus)FA was positively related to MoCA and FDST, but was negatively related to TMT-A. ClausMD was negatively correlated with MoCA and language fluency. Koedam score was positively correlated with CDR-SB, ExcapMD, and ClausMD, but negatively correlated with MMSE score and inverse BDST.
The central cholinergic system is involved in the cognitive impairment of both aMCI and vMCI, and their mechanisms may be distinct. aMCI patients may present with primary CCP impairment while vMCI patients probably exhibit impairment secondary to vasogenic damage to the cholinergic system projection network. The lateral cholinergic pathway was more severely impaired than the medial pathway in vMCI patients, in addition to being associated with decreased executive and general cognitive functions. The damage to CCP was related to the degree of brain atrophy, and both may be involved in the development and progression of cognitive dysfunction.
探讨中枢胆碱能系统在遗忘型轻度认知障碍（aMCI）和轻度血管性认知障碍（vMCI）中的作用。
纳入 25 例 aMCI 患者、25 例 vMCI 患者和 25 名健康对照者。所有参与者均进行了一系列认知功能量表检查，并接受了脑 MRI 检查。我们分析了各组间神经心理学损伤的差异，以及与神经心理学评分相关的脑萎缩程度和中枢胆碱能通路（CCP）的微观结构变化。
（1）三组的神经心理学特征：对照组的 MoCA 评分、即刻记忆、延迟回忆、线索回忆、长时延迟识别和 CDR-SB 明显优于 aMCI 和 vMCI 组。aMCI 组的即刻记忆、延迟记忆、线索回忆、长时延迟识别和 FDST 的 Forward 得分低于 vMCI 组。与 aMCI 组相比，vMCI 组在 TMA-A、TMT-B 和 TMT B-A 上的延迟时间更长。vMCI 和 aMCI 组之间 HAMA、HAMD、MMSE、MoCA、波士顿命名测验（BNT）、语言流畅性或后部萎缩的视觉量表（Koedam 评分）无显著差异。（2）CCP 微观结构变化：与其他两组相比，vMCI 组内侧通路扣带束（Cing）的 FA 值降低，外侧通路外囊（Excap）的 MD 值升高。此外，vMCI 组的 CingMD 值高于对照组，但与 aMCI 组相比差异不明显。（3）最后，我们对所有参与者进行了偏相关分析，研究了 CCP 的微观结构变化、脑萎缩程度和神经心理学评分。CingFA 与 TMT-B、B-A 和 FDST 呈负相关。CingMD 与 FDST 呈负相关。ExcapFA 与 MMSE 和 BDST 的 Backward 呈正相关，而 ExcapMD 与 MMSE 和 MoCA 呈负相关。屏状核（Claus）FA 与 MoCA 和 FDST 呈正相关，与 TMT-A 呈负相关。ClausMD 与 MoCA 和语言流畅性呈负相关。Koedam 评分与 CDR-SB、ExcapMD 和 ClausMD 呈正相关，与 MMSE 评分和逆 BDST 呈负相关。
中枢胆碱能系统参与了 aMCI 和 vMCI 的认知障碍，其机制可能不同。aMCI 患者可能表现为 CCP 原发性损伤，而 vMCI 患者可能表现为胆碱能系统投射网络的血管源性损伤引起的继发性损伤。与内侧通路相比，vMCI 患者的外侧胆碱能通路损伤更严重，与执行功能和一般认知功能下降有关。CCP 的损伤与脑萎缩程度有关，两者都可能参与认知功能障碍的发生和发展。
