Tang Maoping, Shi Shi, Guo Yubing, Xu Wangjie, Wang Lianyun, Chen Yi, Wang Zhaoxia, Qiao Zhongdong
School of Life Science and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240, China.
School of Life Science and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240, China.
Neuropharmacology. 2014 Jun;81:256-66. doi: 10.1016/j.neuropharm.2014.02.008. Epub 2014 Feb 21.
Aggregation of amyloid-beta (Aβ) fragments is one of the major pathological hallmarks of Alzheimer's disease (AD). Our previous study has demonstrated that a novel compound named N-[2-(3, 4-dimethoxyphenyl) ethyl]-3-phenyl-acrylamide (gx-50) can decrease the accumulation of Aβ oligomers in the cerebral cortex and improve the cognitive abilities in transgenic demented mice. To further study the mechanism of the neuroprotective effect of gx-50 against AD, we employed microarray to investigate the gene expression profile of the primary cultured neurons treated with gx-50 or/and Aβ. Microarray disclosed 351 genes associated with AD in the gx-50 plus Aβ treated group, out of the 22,523 probes. 217 of the 351 genes were significantly up-regulated, 134 of them were down-regulated. The 351 genes were mainly involved in neurotransmission, signal transduction, nervous system development, protein phosphorylation, transcription and apoptosis. By the Onto-pathway analysis, a network involved two molecules - GSK-3, CREB and another two closely linked proteins - AKT, BDNF was discovered. The GSK/CREB pathway was further studied at the gene and protein level both in vivo and in vitro. Western blot and immunohistochemistry analysis showed that the gx-50 elevated the AKT phosphorylation and inhibited its downstream protein - GSK-3's activity, then restored the CREB's transcriptional activity, and finally enhanced the expression of the CREB target gene - BDNF. In addition, the real-time PCR results displayed the same tendency. In conclusion, studies in this research indicated that the gx-50 may improve the cognitive ability of AD via the GSK-3/CREB pathway.
淀粉样β蛋白（Aβ）片段的聚集是阿尔茨海默病（AD）的主要病理特征之一。我们之前的研究表明，一种名为N-[2-(3,4-二甲氧基苯基)乙基]-3-苯基丙烯酰胺（gx-50）的新型化合物可以减少转基因痴呆小鼠大脑皮质中Aβ寡聚体的积累，并改善其认知能力。为了进一步研究gx-50对AD神经保护作用的机制，我们采用基因芯片技术研究了用gx-50或/和Aβ处理的原代培养神经元的基因表达谱。基因芯片在22523个探针中揭示了gx-50加Aβ处理组中351个与AD相关的基因。351个基因中有217个显著上调，134个下调。这351个基因主要参与神经传递、信号转导、神经系统发育、蛋白质磷酸化、转录和细胞凋亡。通过通路分析，发现了一个涉及两个分子——GSK-3、CREB以及另外两个紧密相连的蛋白质——AKT、BDNF的网络。在体内和体外对GSK/CREB通路进行了进一步的基因和蛋白质水平研究。蛋白质免疫印迹和免疫组织化学分析表明，gx-50可提高AKT磷酸化水平并抑制其下游蛋白——GSK-3的活性，进而恢复CREB的转录活性，最终增强CREB靶基因——BDNF的表达。此外，实时定量PCR结果也显示出相同的趋势。总之，本研究表明gx-50可能通过GSK-3/CREB通路改善AD的认知能力。
