Activation of calpain in cultured neurons overexpressing Alzheimer amyloid precursor protein
Activation of calpain in cultured neurons overexpressing Alzheimer amyloid precursor protein
复制标题
DOI：
10.1016/s0169-328x(02)00489-8
复制
发表时间：
2002-11-15
期刊：
影响因子：
--
通讯作者：
Yoshikawa, K
中科院分区：
文献类型：
--
作者：
Kuwako, K;Nishimura, I;Yoshikawa, K
我们之前曾报道过，在体内和体外，有丝分裂后神经元中野生型淀粉样前体蛋白（APP）的过度表达都会诱导 caspase-3 的裂解依赖性激活。在这项研究中。我们利用腺病毒介导的基因转移至有丝分裂后神经元（来源于前人胚胎癌 NT2 细胞），研究了 APP 诱导 caspase-3 激活的机制。在 NT2 衍生神经元中激活 caspase-3 之前，野生型 APP 的过表达显着增加了细胞内 Ca-45(2+) 含量。细胞内 Ca2+ 的螯合显着抑制了 APP 诱导的 caspase-3 激活。此外，钙蛋白酶（一种 Ca2+ 依赖性半胱氨酸蛋白酶）在过度表达 APP 的神经元中被激活，通过钙蛋白酶裂解的 α-胞嘧啶和自溶性 mu-钙蛋白酶片段水平的增加来评估。在表达 Abeta(1-20) 结构域缺陷的 APP 突变体的神经元中，钙蛋白酶和 caspase-3 均未激活。钙蛋白酶抑制剂几乎完全抑制 APP 诱导的神经元 caspase-3 激活。 E64d，钙蛋白酶的膜渗透性抑制剂。显着抑制 APP 诱导的神经元死亡。这些结果表明野生型 APP 的过度表达会激活钙蛋白酶，从而介导有丝分裂后神经元中的 caspase-3 激活。 (C) 2002 Elsevier Science B.V. 保留所有权利。
We have previously reported that overexpression of wild-type amyloid precursor protein (APP) in postmitotic neurons induces cleavage-dependent activation of caspase-3 both in vivo and in vitro. In this study. we investigated the mechanism underlying APP-induced caspase-3 activation using adenovirus-mediated gene transfer into postmitotic neuron,, derived front human embryonal carcinoma NT2 cells. Overexpression of wild-type APP significantly increased intracellular Ca-45(2+) content prior to the activation of caspase-3 in NT2-derived neurons. Chelation of intracellulax Ca2+ markedly suppressed APP-induced activation of caspase-3. Furthermore, calpain, a Ca2+-dependent cysteine protease, was activated in neurons overexpressing APP as assessed by increased levels of calpain-cleaved alpha-fodrin and autolytic mu-calpain fragments. Neither calpain nor caspase-3 was activated in neuron,., expressing an APP mutant defective in the Abeta(1-20) domain. Calpain inhibitors almost completely suppressed APP-induced activation of neuronal caspase-3. E64d, a membrane permeable inhibitor of calpain. significantly suppressed APP-induced neuronal death. These results suggest that overexpression of wild-type APP activates calpain that mediates caspase-3 activation in postmitotic neurons. (C) 2002 Elsevier Science B.V. All rights reserved.