Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Department of Pathophysiology, Weifang Medical University, Weifang, 261053, China.
Neurotherapeutics. 2020 Jul;17(3):1271-1286. doi: 10.1007/s13311-020-00859-w.
Schizophrenia (SZ) is a serious mental condition and is associated with cognitive impairments. Brain-derived neurotrophic factor (BDNF) is one of the learning- and memory-related molecules found in the CNS and its level was reported to be reduced in SZ brain, while ω-3 polyunsaturated fatty acids (ω-3PUFAs) could improve SZ symptoms, but its mechanism of action remains unknown. Using MK801 injection-induced SZ rat model, we here found that supplementation with ω-3PUFAs improved the levels of p-CREB, BDNF, and p-TrkB in the brain of SZ rats, and restore hippocampal neuronal damage, thereby reducing cognitive impairments in SZ rats. However, overexpression of AAV9/CREB S133A (CREB inactivated mutation) downregulated BDNF/TrkB signaling pathway and remarkably abolished the preventive effect of ω-3PUFAs in MK801-induced schizophrenia. Interestingly, AAV9/CREB S133D (CREB activated mutation) improved synaptic dysfunctions and cognitive defects in MK801 rats. In conclusion, these findings indicate that MK801-induced SZ lesions dephosphorylate CREB at Ser133 site, leading to neuron damage, and ω-3PUFAs improve SZ cognitive impairments by upregulating the CREB/BDNF/TrkB pathway, which provides new clues for the mechanism of SZ cognitive impairments, and a basis for therapeutic intervention.
精神分裂症(SZ)是一种严重的精神疾病,与认知障碍有关。脑源性神经营养因子(BDNF)是中枢神经系统中与学习和记忆相关的分子之一,据报道,SZ 大脑中的 BDNF 水平降低,而 ω-3 多不饱和脂肪酸(ω-3PUFAs)可以改善 SZ 症状,但作用机制尚不清楚。我们使用 MK801 注射诱导的 SZ 大鼠模型,发现 ω-3PUFAs 的补充改善了 SZ 大鼠大脑中 p-CREB、BDNF 和 p-TrkB 的水平,并恢复海马神经元损伤,从而减轻 SZ 大鼠的认知障碍。然而,AAV9/CREB S133A(CREB 失活突变)的过表达下调了 BDNF/TrkB 信号通路,并显著消除了 ω-3PUFAs 在 MK801 诱导的精神分裂症中的预防作用。有趣的是,AAV9/CREB S133D(CREB 激活突变)改善了 MK801 大鼠的突触功能障碍和认知缺陷。总之,这些发现表明,MK801 诱导的 SZ 病变使 CREB 在 Ser133 位点去磷酸化,导致神经元损伤,而 ω-3PUFAs 通过上调 CREB/BDNF/TrkB 通路改善 SZ 认知障碍,为 SZ 认知障碍的机制提供了新的线索,并为治疗干预提供了依据。