Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Professor Gama Pinto, 1649-003, Lisbon, Portugal.
Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Professor Gama Pinto, 1649-003, Lisbon, Portugal; Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal.
Exp Cell Res. 2020 Oct 15;395(2):112209. doi: 10.1016/j.yexcr.2020.112209. Epub 2020 Jul 30.
Astrocytes are major contributors of motor neuron (MN) degeneration in amyotrophic lateral sclerosis (ALS). We investigated whether regional and cell maturation differences influence ALS astrocyte malfunction. Spinal and cortical astrocytes from SOD1G93A (mSOD1) 7-day-old mice were cultured for 5 and 13 days in vitro (DIV). Astrocyte aberrancies predominated in 13DIV cells with region specificity. 13DIV cortical mSOD1 astrocytes showed early morphological changes and a predominant reactive and inflammatory phenotype, while repressed proteins and genes were found in spinal cells. Inflammatory-associated miRNAs, e.g. miR-155/miR-21/miR-146a, were downregulated in the first and upregulated in the later ones. Interestingly, depleted miR-155/miR-21/miR-146a in small extracellular vesicles (sEVs/exosomes) was a common pathological feature. Cortical mSOD1 astrocytes induced late apoptosis and kinesin-1 downregulation in mSOD1 NSC-34 MNs, whereas spinal cells upregulated dynein, while decreased nNOS and synaptic-related genes. Both regional-distinct mSOD1 astrocytes enhanced iNOS gene expression in mSOD1 MNs. We provide information on the potential contribution of astrocytes to ALS bulbar-vs. spinal-onset pathology, local influence on neuronal dysfunction and their shared miRNA-depleted exosome trafficking. These causal and common features may have potential therapeutic implications in ALS. Future studies should clarify if astrocyte-derived sEVs are active players in ALS-related neuroinflammation and glial activation.
星形胶质细胞是肌萎缩侧索硬化症（ALS）中运动神经元（MN）变性的主要贡献者。我们研究了区域和细胞成熟度差异是否会影响 ALS 星形胶质细胞功能障碍。从 SOD1G93A（mSOD1）7 天大的小鼠中分离出脊髓和皮质星形胶质细胞，并在体外培养 5 和 13 天（DIV）。13DIV 皮质 mSOD1 星形胶质细胞表现出早期形态变化和以反应性和炎症表型为主，而脊髓细胞中发现了抑制蛋白和基因。炎症相关的 microRNA，如 miR-155/miR-21/miR-146a，在早期下调，而在晚期上调。有趣的是，小细胞外囊泡（sEVs/exosomes）中 miR-155/miR-21/miR-146a 的耗竭是一种共同的病理特征。皮质 mSOD1 星形胶质细胞诱导 mSOD1 NSC-34 MNs 晚期凋亡和驱动蛋白-1 下调，而脊髓细胞上调动力蛋白，同时降低 nNOS 和突触相关基因。两种区域特异性 mSOD1 星形胶质细胞均增强了 mSOD1 MNs 中 iNOS 基因的表达。我们提供了关于星形胶质细胞对 ALS 延髓-脊髓发病机制潜在贡献的信息，以及对神经元功能障碍的局部影响及其共同的 microRNA 耗竭外体转运。这些因果和共同特征可能在 ALS 中具有潜在的治疗意义。未来的研究应阐明星形胶质细胞衍生的 sEVs 是否是 ALS 相关神经炎症和神经胶质激活的活跃参与者。
