a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark.
b Department of Pathology , Odense University Hospital , Odense , Denmark.
Nanotoxicology. 2019 Mar;13(2):221-239. doi: 10.1080/17435390.2018.1540728. Epub 2019 Jan 9.
Silver nanoparticles (AgNPs) have been reported to penetrate the central nervous system (CNS) and induce neurotoxicity. However, there is a paucity of understanding of the toxicity of AgNPs and their effect on the blood-brain barrier (BBB) including the underlying molecular mechanism(s) of action. Such information is important for the formulation of new strategies for delivery of biological therapeutics to central nervous system (CNS) targets. Using an in vitro BBB model and mass spectrometry-based proteomics, we investigated alterations in the proteomes of brain endothelial cells and astrocytes at different time points after AgNPs exposure (24 and 48 h). Our data showed that several proteins involved in neurodisorders and neurodegeneration were significantly upregulated in endothelial cells (e.g. 7-dehydrocholesterol reductase, zinc transporters 1 and 6), while proteins responsible for maintaining brain homeostasis were significantly downregulated (e.g anti-oxidative proteins glutathione peroxidase 1 and glutathione peroxidase 4). Many inflammatory pathways were significantly upregulated at 24 h post-AgNPs exposure (C9 pathway), while at 48 h proteins involved in BBB damage and anti-inflammatory responses were upregulated (quinoneoxidoreductase1 and glutamate cysteine ligase catalytic subunit) suggesting that by the later time point, cellular protection pathways had been activated to rescue the cells from AgNPs-induced toxicity. Our study suggests that in the initial stage of exposure, AgNPs exerted direct cellular stress on the endothelial cells by triggering a pro-inflammatory cascade. This study provides detailed insight into the toxic potency of AgNPs on in vitro BBB model and adds to the understanding of the adaptive role of BBB with regards to AgNPs-mediated toxicity.
银纳米颗粒（AgNPs）已被报道能穿透中枢神经系统（CNS）并诱导神经毒性。然而，人们对 AgNPs 的毒性及其对血脑屏障（BBB）的影响，包括其潜在的作用机制，知之甚少。这些信息对于制定新的策略，将生物治疗药物递送到中枢神经系统（CNS）靶点非常重要。本研究使用体外 BBB 模型和基于质谱的蛋白质组学，研究了 AgNPs 暴露后不同时间（24 和 48 小时）脑内皮细胞和星形胶质细胞蛋白质组的变化。我们的数据表明，几种与神经紊乱和神经退行性疾病相关的蛋白质在血管内皮细胞中显著上调（例如 7-脱氢胆固醇还原酶、锌转运蛋白 1 和 6），而负责维持大脑内环境稳定的蛋白质则显著下调（例如抗氧化蛋白谷胱甘肽过氧化物酶 1 和谷胱甘肽过氧化物酶 4）。许多炎症途径在 AgNPs 暴露后 24 小时显著上调（C9 途径），而在 48 小时时，与 BBB 损伤和抗炎反应相关的蛋白质上调（醌氧化还原酶 1 和谷氨酰胺半胱氨酸连接酶催化亚基），这表明在稍后的时间点，细胞保护途径已被激活，以拯救细胞免受 AgNPs 诱导的毒性。我们的研究表明，在暴露的初始阶段，AgNPs 通过触发促炎级联反应，直接对内皮细胞造成细胞应激。本研究详细了解了 AgNPs 对体外 BBB 模型的毒性作用，并增加了对 BBB 对 AgNPs 介导的毒性的适应性作用的理解。
