Feng D, Wang W, Dong Y, Wu L, Huang J, Ma Y, Zhang Z, Wu S, Gao G, Qin H
Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.
Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.
Neuroscience. 2014 May 30;268:21-32. doi: 10.1016/j.neuroscience.2014.02.053. Epub 2014 Mar 12.
Early brain injury (EBI) after subarachnoid hemorrhage (SAH) is characterized by a reduction in excitatory amino acid transporter 2 (EAAT2) expression and severe amino acid excitotoxicity. The aim of this study was to explore the neuroprotective effect of ceftriaxone (CEF), a potent compound that up-regulates EAAT2, against EBI and the potential mechanisms using in vitro experiments and a rat model of SAH. Intracisternal treatment with CEF significantly improved neurological outcomes and alleviated extracellular glutamate accumulation after SAH. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) staining and Western blot analysis of cleaved caspase 3 showed that CEF decreased hippocampal neuronal apoptosis following SAH. Immunofluorescent staining and Western blotting revealed that CEF significantly reversed the down-regulation of EAAT2 expression following SAH. In Morris water maze (MWM) tests, CEF remarkably ameliorated the SAH-induced cognitive dysfunction in spatial learning memory and reference memory. CEF promoted the nuclear translocation of p65 as well as the activation of Akt in hippocampal astrocytes in vitro and in vivo. These findings suggest that CEF may exert significant protective effects against EBI following SAH by modulating the PI3K/Akt/NF-κB signaling pathway.
蛛网膜下腔出血(SAH)后的早期脑损伤(EBI)的特征是兴奋性氨基酸转运体2(EAAT2)表达降低和严重的氨基酸兴奋性毒性。本研究的目的是利用体外实验和SAH大鼠模型,探讨头孢曲松(CEF)这种上调EAAT2的有效化合物对EBI的神经保护作用及其潜在机制。SAH后经脑池内给予CEF可显著改善神经功能结局并减轻细胞外谷氨酸积累。末端脱氧核苷酸转移酶介导的dUTP生物素缺口末端标记法(TUNEL)染色和裂解的半胱天冬酶3的蛋白质印迹分析表明,CEF可减少SAH后海马神经元凋亡。免疫荧光染色和蛋白质印迹显示,CEF可显著逆转SAH后EAAT2表达的下调。在莫里斯水迷宫(MWM)试验中,CEF显著改善了SAH诱导的空间学习记忆和参考记忆方面的认知功能障碍。CEF在体外和体内均可促进海马星形胶质细胞中p65的核转位以及Akt的激活。这些发现表明,CEF可能通过调节PI3K/Akt/NF-κB信号通路对SAH后的EBI发挥显著的保护作用。