Tianjin Medical University First Center Clinical College, Tianjin, China.
Department of Anesthesiology, Tianjin First Center Hospital, Tianjin, China.
Neuroscience. 2018 Nov 1;391:1-12. doi: 10.1016/j.neuroscience.2018.08.034. Epub 2018 Sep 11.
Hepatic ischemia reperfusion (HIR) has been found to induce hippocampus injury and cognitive dysfunction. The N-methyl-d-aspartate (NMDA) receptor subunit 2A (NR2A) is an important factor mediating excitotoxicity and neurons injury, and autophosphorylation of Src can up-regulate tyrosine phosphorylation of NR2A to improve its activity. However, the role of Src and NR2A in HIR-induced hippocampus injury in young mice remains unknown. In this study, we found that serum biomarkers of brain injury (S100β and NSE) increased significantly and reached highest after reperfusion of 3 days which had the same trend with the levels of p-Src and p-NR2A. Interactions between Src and NR2A or PSD95 were increased after HIR. Hippocampal neuron apoptosis was increased, and long-term cognitive impairment was found after reperfusion of 1 month. Inhibition of Src and NR2A with PP2 and NVP-AAM077 respectively not only down-regulated the levels of p-Src and p-NR2A, but also ameliorated hippocampal neurons apoptosis and long-term cognitive impairment after HIR. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor α (TNF-α), interferon-γ (IFN-γ) and interleukin (IL)-6 were increased after reperfusion of 3 days, while PP2 and NVP-AAM077 treatment didn't attenuate the changes. And no difference was found in serum TNF-α, IFN-γ, IL-6 concentrations as well as the levels of Src, p-Src, NR2A, p-NR2A, PSD95 among the four groups after reperfusion of 1 month. In summary, HIR can lead to hippocampus injury and long-term cognitive dysfunction, and Src-PSD95-NR2A pathway plays an important role in the process.
肝缺血再灌注(HIR)已被发现可诱导海马损伤和认知功能障碍。N-甲基-D-天冬氨酸(NMDA)受体亚单位 2A(NR2A)是介导兴奋性毒性和神经元损伤的重要因素,Src 的自身磷酸化可以上调 NR2A 的酪氨酸磷酸化,从而提高其活性。然而,Src 和 NR2A 在年轻小鼠 HIR 诱导的海马损伤中的作用尚不清楚。在这项研究中,我们发现脑损伤的血清生物标志物(S100β 和 NSE)在再灌注 3 天后显著增加,达到最高水平,这与 p-Src 和 p-NR2A 的水平呈相同趋势。HIR 后 Src 和 NR2A 或 PSD95 之间的相互作用增加。海马神经元凋亡增加,再灌注 1 个月后发现长期认知障碍。分别用 PP2 和 NVP-AAM077 抑制 Src 和 NR2A,不仅下调了 p-Src 和 p-NR2A 的水平,而且改善了 HIR 后海马神经元凋亡和长期认知障碍。再灌注 3 天后血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、肿瘤坏死因子-α(TNF-α)、干扰素-γ(IFN-γ)和白细胞介素(IL)-6 升高,而 PP2 和 NVP-AAM077 治疗并不能减轻这些变化。再灌注 1 个月后,四组间血清 TNF-α、IFN-γ、IL-6 浓度以及 Src、p-Src、NR2A、p-NR2A、PSD95 水平均无差异。总之,HIR 可导致海马损伤和长期认知功能障碍,Src-PSD95-NR2A 通路在该过程中起重要作用。