Jensen Pia, Myhre Christa L, Lassen Pernille S, Metaxas Athanasios, Khan Asif M, Lambertsen Kate L, Babcock Alicia A, Finsen Bente, Larsen Martin R, Kempf Stefan J
Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
Oncotarget. 2017 Jul 21;8(36):60223-60242. doi: 10.18632/oncotarget.19428. eCollection 2017 Sep 1.
Neuroinflammation is a hallmark of Alzheimer's disease and TNFα as the main inducer of neuroinflammation has neurodegenerative but also pro-regenerative properties, however, the dose-dependent molecular changes on signaling pathway level are not fully understood. We performed quantitative proteomics and phospho-proteomics to target this point. In HT22 cells, we found that TNFα reduced mitochondrial signaling and inhibited mTOR protein translation signaling but also led to induction of neuroprotective MAPK-CREB signaling. Stimulation of human neurons with TNFα revealed similar cellular mechanisms. Moreover, a number of synaptic plasticity-associated genes were altered in their expression profile including . SiRNA-mediated knockdown of CREB in human neurons prior to TNFα stimulation led to a reduced number of protein/phospho-protein hits compared to siRNA-mediated knockdown of CREB or TNFα stimulation alone and countermeasured the reduced CREB signaling. data of TNFα knockout mice showed that learning ability did not depend on TNFα per se but that TNFα was essential for preserving the learning ability after episodes of lipopolysaccharide-induced neuroinflammation. This may be based on modulation of CREB/CREB signaling as revealed by the / data. Our data show that several molecular targets and signaling pathways induced by TNFα in neurons resemble those seen in Alzheimer's disease pathology.
神经炎症是阿尔茨海默病的一个标志,作为神经炎症主要诱导因子的肿瘤坏死因子α(TNFα)具有神经退行性变特性,但也具有促再生特性,然而,其在信号通路水平上剂量依赖性的分子变化尚未完全明确。我们开展了定量蛋白质组学和磷酸化蛋白质组学研究来探讨这一问题。在HT22细胞中,我们发现TNFα降低了线粒体信号传导并抑制了mTOR蛋白翻译信号传导,但也导致了神经保护相关的丝裂原活化蛋白激酶-环磷腺苷效应元件结合蛋白(MAPK-CREB)信号传导的诱导。用TNFα刺激人类神经元显示出类似的细胞机制。此外,一些与突触可塑性相关的基因在其表达谱上发生了改变,包括……在TNFα刺激之前,用小干扰RNA(siRNA)介导的人类神经元中CREB基因敲低与单独使用siRNA介导的CREB基因敲低或TNFα刺激相比,导致蛋白质/磷酸化蛋白质命中数减少,并对抗了CREB信号传导的降低。TNFα基因敲除小鼠的数据表明,学习能力本身并不依赖于TNFα,但TNFα对于在脂多糖诱导的神经炎症发作后维持学习能力至关重要。这可能基于如……数据所揭示的CREB/CREB信号传导的调节。我们的数据表明,TNFα在神经元中诱导的几个分子靶点和信号通路类似于在阿尔茨海默病病理学中所见的那些。