Tian Jiaqi, Zhang Yuwen, Liu Le, Li Chaofan, Hao Xiaozhu
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
College of Health Science and Technology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Front Neurosci. 2025 Aug 5;19:1566957. doi: 10.3389/fnins.2025.1566957. eCollection 2025.
This study aimed to evaluate the dynamic changes of the perivascular space diffusion index (index for diffusivity along the perivascular space, ALPS) and its relationship with aquaporin 4 (AQP4) polarization after cerebral ischemia in rats.
Rats were subjected to transient middle cerebral artery occlusion (tMCAO) and evaluated at 1, 3, 7, 14, and 28 days post-ischemia using diffusion tensor imaging (DTI), T2-weighted imaging (T2WI), and susceptibility-weighted imaging (SWI). The ALPS index was determined from imaging data, focusing on periventricular and corpus callosum/cingulate regions. Brains were analyzed for AQP4 and glial fibrillary acidic protein (GFAP) via immunofluorescence.
The results showed that ischemic rats displayed reduced ALPS indexes, particularly on the ipsilateral side, with an initial decrease at day 1 and subsequent recovery by days 14 and 28. AQP4 polarization in the non-glial scar area around the infarction followed a similar pattern, demonstrating that there was a concordant trend between the ALPS index and AQP4 polarization status.
In conclusion, the ALPS index can reflect changes in AQP4-mediated glymphatic pathway function, suggesting a significant decline in the hyperacute phase and a notable recovery in the early chronic phase, which may have implications for stroke therapeutic strategies.
本研究旨在评估大鼠脑缺血后血管周围间隙扩散指数（沿血管周围间隙的扩散率指数，ALPS）的动态变化及其与水通道蛋白4（AQP4）极化的关系。
对大鼠进行短暂性大脑中动脉闭塞（tMCAO），并在缺血后1、3、7、14和28天使用扩散张量成像（DTI）、T2加权成像（T2WI）和磁敏感加权成像（SWI）进行评估。从成像数据中确定ALPS指数，重点关注脑室周围和胼胝体/扣带回区域。通过免疫荧光分析大脑中的AQP4和胶质纤维酸性蛋白（GFAP）。
结果显示，缺血大鼠的ALPS指数降低，尤其是在同侧，在第1天开始下降，随后在第14天和28天恢复。梗死周围非胶质瘢痕区域的AQP4极化遵循类似模式，表明ALPS指数与AQP4极化状态之间存在一致趋势。
总之，ALPS指数可以反映AQP4介导的类淋巴途径功能的变化，表明在超急性期显著下降，在慢性早期显著恢复，这可能对中风治疗策略有影响。
