Laboratory of Psychiatry and Experimental Alzheimer's Research, Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria.
Laboratory for Translational Neurodegeneration Research, Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innrain 66, A-6020 Innsbruck, Austria.
Biomolecules. 2022 Jan 19;12(2):163. doi: 10.3390/biom12020163.
The accumulation of α-synuclein (α-syn) in the brain plays a role in synucleinopathies and it is hypothesized to spread in a prion-like fashion between connected brain regions. In the present study, we aim to investigate this spreading in well-characterized sagittal organotypic whole brain slices taken from postnatal wild type (WT) and transgenic mice overexpressing human α-syn under the promoter of proteolipid protein (PLP). Collagen hydrogels were loaded with monomers of human α-syn, as well as human and mouse pre-formed fibrils (PFFs), to allow local application and slow release. The spreading of α-syn was evaluated in different brain regions by immunohistochemistry for total α-syn and α-syn phosphorylated at the serine129 position (α-syn-P). The application of human and mouse PFFs of α-syn caused the aggregation and spreading of α-syn-P in the brain slices, which was pronounced the most at the region of hydrogel application and surrounding striatum, as well as along the median forebrain bundle. The organotypic slices from transgenic mice showed significantly more α-syn pathology than those from WT mice. The present study demonstrates that seeding with α-syn PFFs but not monomers induced intracellular α-syn pathology, which was significantly more prominent in brain slices with α-syn overexpression. This is consistent with the prion-like spreading theory of α-syn aggregates. The sagittal whole brain slices characterized in this study carry the potential to be used as a novel model to study α-syn pathology.
α-突触核蛋白（α-syn）在大脑中的积累在突触核蛋白病中起作用，并且据推测它以类朊病毒的方式在连接的脑区之间传播。在本研究中，我们旨在研究从过表达人α-突触核蛋白的新生野生型（WT）和转基因小鼠中获得的特征良好的矢状器官型全脑切片中的这种传播，该蛋白由蛋白脂质蛋白（PLP）启动子驱动。胶原蛋白水凝胶中加载了人α-突触核蛋白的单体，以及人和鼠预形成纤维（PFF），以允许局部应用和缓慢释放。通过免疫组织化学检测总α-突触核蛋白和丝氨酸 129 位磷酸化的α-突触核蛋白（α-syn-P），在不同脑区评估α-syn 的传播。人α-突触核蛋白和鼠α-突触核蛋白 PFF 的应用导致脑切片中α-syn-P 的聚集和传播，在水凝胶应用部位及其周围纹状体以及中脑束沿线最为明显。转基因小鼠的器官型切片显示出比 WT 小鼠明显更多的α-突触核蛋白病理。本研究表明，用α-syn PFF 而不是单体接种可诱导细胞内α-syn 病理学，在α-syn 过表达的脑切片中更为明显。这与α-突触核蛋白聚集的类朊病毒传播理论一致。本研究中所描述的矢状全脑切片具有作为研究α-syn 病理学的新型模型的潜力。
