Xie Nanchang, Li Yingjiao, Wang Cui, Lian Yajun, Zhang Haifeng, Li Yujuan, Meng Xianghe, Du Liyuan
Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Cell Mol Neurobiol. 2020 Nov;40(8):1297-1305. doi: 10.1007/s10571-020-00814-5. Epub 2020 Feb 21.
Autophagy plays a critical role in epileptic neuronal injury, and recent studies have demonstrated that FAM134B plays an important role in regulating autophagy. However, the effect of FAM134B on epileptic neuronal injury remains unclear. In this study, we investigated the role of FAM134B in neuronal apoptosis and endoplasmic reticulum (ER) stress using the hippocampal neuronal culture model of acquired epilepsy (AE) in vitro. We found that in this model, the level of autophagy significantly increased, indicated by an elevated LC3-II/LC3-I ratio. FAM134B overexpression using lentiviral vectors enhanced autophagy, whereas FAM134B downregulation using lentiviral vectors impaired this process. In addition, the ER Ca concentration was decreased and the intracellular level of reactive oxygen species was increased in this model. FAM134B overexpression was sufficient to reverse these changes. Moreover, FAM134B overexpression attenuated ER stress as shown by a decrease in the expression of C/-EBP homologous protein and glucose-regulated protein 78, and neuronal apoptosis induced by seizure, while FAM134B downregulation caused the opposite effects. Further, pre-treatment with the selective autophagy inhibitor 3-methyladenine abolished the effects of FAM134B on ER stress and neuronal apoptosis. Altogether, we demonstrate that FAM134B is an important regulator of AE-induced ER stress and neuronal apoptosis by controlling autophagy function.
自噬在癫痫性神经元损伤中起关键作用，最近的研究表明FAM134B在调节自噬中起重要作用。然而，FAM134B对癫痫性神经元损伤的影响仍不清楚。在本研究中，我们使用体外获得性癫痫（AE）的海马神经元培养模型，研究了FAM134B在神经元凋亡和内质网（ER）应激中的作用。我们发现在该模型中，自噬水平显著增加，以LC3-II/LC3-I比值升高为指标。使用慢病毒载体过表达FAM134B增强了自噬，而使用慢病毒载体下调FAM134B则损害了这一过程。此外，该模型中内质网钙浓度降低，细胞内活性氧水平升高。FAM134B过表达足以逆转这些变化。此外，FAM134B过表达减轻了内质网应激，表现为C/EBP同源蛋白和葡萄糖调节蛋白78的表达降低，以及癫痫发作诱导的神经元凋亡，而FAM134B下调则产生相反的效果。此外，用选择性自噬抑制剂3-甲基腺嘌呤预处理消除了FAM134B对内质网应激和神经元凋亡的影响。总之，我们证明FAM134B通过控制自噬功能，是AE诱导的内质网应激和神经元凋亡的重要调节因子。
