Zhou Liang, Yang Wenxia, Liu Yang, Zheng Yu, Ge Xin, Ai Kai, Liu Guangyao, Zhang Jing
Department of Magnetic Resonance, The Second Hospital of Lanzhou University, Lanzhou, China.
Second Clinical Medical School, Lanzhou University, Lanzhou, China.
Front Aging Neurosci. 2024 May 2;16:1399943. doi: 10.3389/fnagi.2024.1399943. eCollection 2024.
This research aims to investigate putative mechanisms between glymphatic activity and cognition in mild cognitive impairment (MCI) and analyzes whether the relationship between cognitive reserve (CR) and cognition was mediated by glymphatic activity.
54 MCI patients and 31 NCs were enrolled to evaluate the bilateral diffusivity along the perivascular spaces and to acquire an index for diffusivity along the perivascular space (ALPS-index) on diffusion tensor imaging (DTI). The year of education was used as a proxy for CR. The ALPS-index was compared between two groups and correlation analyses among the ALPS-index, cognitive function, and CR were conducted. Mediation analyses were applied to investigate the correlations among CR, glymphatic activity and cognition.
MCI group had a significantly lower right ALPS-index and whole brain ALPS-index, but higher bilateral diffusivity along the y-axis in projection fiber area (Dyproj) than NCs. In MCI group, the left Dyproj was negatively related to cognitive test scores and CR, the whole brain ALPS-index was positively correlated with cognitive test scores and CR. Mediation analysis demonstrated that glymphatic activity partially mediated the correlations between CR and cognitive function.
MCI exhibited decreased glymphatic activity compared to NCs. CR has a protective effect against cognitive decline in MCI, and this effect may be partially mediated by changes in glymphatic activity.
本研究旨在探讨轻度认知障碍（MCI）患者中脑淋巴系统活性与认知之间的潜在机制，并分析认知储备（CR）与认知之间的关系是否由脑淋巴系统活性介导。
招募54例MCI患者和31例正常对照（NCs），在扩散张量成像（DTI）上评估沿血管周围间隙的双侧扩散率，并获得血管周围间隙扩散率指数（ALPS指数）。以受教育年限作为CR的替代指标。比较两组之间的ALPS指数，并对ALPS指数、认知功能和CR进行相关性分析。应用中介分析来研究CR、脑淋巴系统活性和认知之间的相关性。
MCI组右侧ALPS指数和全脑ALPS指数显著低于NCs，但在投射纤维区域沿y轴的双侧扩散率（Dyproj）高于NCs。在MCI组中，左侧Dyproj与认知测试分数和CR呈负相关，全脑ALPS指数与认知测试分数和CR呈正相关。中介分析表明，脑淋巴系统活性部分介导了CR与认知功能之间的相关性。
与NCs相比，MCI患者脑淋巴系统活性降低。CR对MCI患者的认知衰退具有保护作用，且这种作用可能部分由脑淋巴系统活性的变化介导。
