Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9JT, UK.
Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9JT, UK; Leeds Trinity University, Brownberrie Lane, Horsforth, Leeds, LS18 5HD, UK.
Neurochem Int. 2018 Sep;118:134-144. doi: 10.1016/j.neuint.2018.04.004. Epub 2018 Apr 10.
Cerebral ischemia is known to be a major cause of death and the later development of Alzheimer's disease and vascular dementia. However, ischemia induced cellular damage that initiates these diseases remain poorly understood. This is primarily due to lack of clinically relevant models that are highly reproducible. Here, we have optimised a murine model of global cerebral ischaemia with multiple markers to determine brain pathology, neurochemistry and correlated memory deficits in these animals. Cerebral ischaemia in mice was induced by bilateral common carotid artery occlusion. Following reperfusion, the mice were either fixed with 4% paraformaldehyde or decapitated under anaesthesia. Brains were processed for Western blotting or immunohistochemistry for glial (GLT1) and vesicular (VGLUT1, VGLUT2) glutamate transporters and paired helical filament (PHF1) tau. The PHF1 tau is the main component of neurofibrillary tangle, which is the pathological hallmark of Alzheimer's disease and vascular dementia. The novel object recognition behavioural assay was used to investigate the functional cognitive consequences in these mice. The results show consistent and selective neuronal and glial cell changes in the hippocampus and the cortex together with significant reductions in GLT1 (***P < 0.001), VGLUT1 (**P < 0.01) and VGLUT2 (***P < 0.001) expressions in the hippocampus in occluded mice as compared to sham-operated animals. These changes are associated with increased PHF1 (***P < 0.0001) protein and a significant impairment of performance (*p < 0.0006, N = 6/group) in the novel object recognition test. This model represents a useful tool for investigating cellular, biochemical and molecular mechanisms of global cerebral ischaemia and may be an ideal preclinical model for vascular dementia.
脑缺血是导致死亡和阿尔茨海默病和血管性痴呆等疾病发展的主要原因。然而，引发这些疾病的缺血性细胞损伤仍知之甚少。这主要是由于缺乏高度可重复的临床相关模型。在这里，我们使用多种标志物优化了一种全脑缺血的小鼠模型，以确定这些动物的脑病理学、神经化学和相关记忆缺陷。通过双侧颈总动脉闭塞诱导小鼠脑缺血。再灌注后，将小鼠用 4%多聚甲醛固定或麻醉下断头。将大脑用于 Western blot 或免疫组织化学分析，以检测胶质（GLT1）和囊泡（VGLUT1、VGLUT2）谷氨酸转运体以及成对螺旋丝（PHF1）tau。PHF1 tau 是神经原纤维缠结的主要成分，而神经原纤维缠结是阿尔茨海默病和血管性痴呆的病理标志。新物体识别行为测定用于研究这些小鼠的功能性认知后果。结果显示，与假手术动物相比，缺血小鼠的海马和皮层中存在一致且选择性的神经元和神经胶质细胞变化，同时 GLT1（***P < 0.001）、VGLUT1（**P < 0.01）和 VGLUT2（***P < 0.001）在海马中的表达显著降低。这些变化与 PHF1 蛋白的增加（***P < 0.0001）以及新物体识别测试中性能的显著受损（*p < 0.0006，N = 6/组）相关。该模型代表了研究全脑缺血的细胞、生化和分子机制的有用工具，可能是血管性痴呆的理想临床前模型。
