Neuroprotective effect of AIP on N-methyl-D-aspartate-induced cell death in retinal neurons
Neuroprotective effect of AIP on N-methyl-D-aspartate-induced cell death in retinal neurons
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DOI：
10.1016/s0169-328x(00)00226-6
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发表时间：
2000-12-28
期刊：
影响因子：
--
通讯作者：
Cooper, NGF
中科院分区：
文献类型：
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作者：
Laabich, A;Cooper, NGF
谷氨酸受体的过度激活介导神经元死亡，但介导这种类型的神经元死亡的细胞内信号通路仅部分了解。以前，我们已经证明，钙/钙调蛋白依赖性蛋白激酶II-α，（CaMK II-α（B）），含有核定位信号，但不CaMK II-α在视网膜神经元暴露于N-甲基-D-天冬氨酸（NMDA）的改变。本研究描述了CaMK Ⅱ-α（B）在导致细胞凋亡的信号转导中的预期功能。用末端脱氧核糖核苷酸转移酶（TdT）介导的生物素16-dUTP缺口末端标记（TUNEL）法检测大鼠视网膜固定组织切片中的DNA片段。TUNEL测定证实，细胞死亡发生在内核和神经节细胞层注射4 mM NMDA后。具有已证实的细胞渗透性的特异性AIP（肉豆蔻酰化autocamtide-2相关抑制肽）在体内抑制CaMKII活性。500 μ M AIP的神经保护作用在给药前2小时完成，并与NMDA应用一致。此外，100 IJ-M的AIP仅部分地防止NMDA诱导的兴奋性毒性。已知参与神经元凋亡的caspase-3（17 kDa）的构象活性片段在30分钟内和注射NMDA后2小时明显。这种激活被抑制500 μ M AIP时，给药前2小时，并与NMDA的应用程序一致。结果表明，CaMKII-α（B）亚型在兴奋性毒性诱导的神经元凋亡中起作用。(C)2000 Elsevier Science B. V.保留所有权利。
Excessive activation of glutamate receptors mediates neuronal death, but the intracellular signaling pathways that mediate this type of neuronal death are only partly understood. Previously, we have demonstrated that calcium/calmodulin-dependent protein kinase II-a, (CaMKII-alpha (B)) containing a nuclear localizing signal but not CaMKII-alpha is altered in retinal neurons exposed to N-methyl-D-aspartate (NMDA). The present study describes a prospective function of CaMKII-alpha (B) in signal transduction leading to apoptosis. The terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labelling (TUNEL) method was used to detect fragmented DNA in fixed tissue sections of rat retina. The TUNEL assay confirmed that cell death occurs in the inner nuclear and ganglion cell layers following injection of 4 mM NMDA. A specific AIP (myristoylated autocamtide-2-related inhibitory peptide) with proven cell permeability inhibits CaMKII activity in vivo. Neuroprotection achieved by 500 muM AIP was complete when administered 2 h before and coincident with the NMDA application. Additionally, 100 IJ-M of AIP protects only partially against the NMDA-induced excitotoxicity. The conformationally active fragment of caspase-3 (17 kDa), known to be involved in neuronal apoptosis was apparent within 30 min and at 2 h postinjection with NMDA. This activation was inhibited by 500 muM AIP when administered 2 h before and coincident with the NMDA application. The results suggest that CaMKII-alpha (B), isoform plays a role in excitotoxicity-induced neuronal apoptosis. (C) 2000 Elsevier Science B.V. All rights reserved.