Amyloid β-protein potentiates tunicamycin-induced neuronal death in organotypic hippocampal slice cultures
Amyloid β-protein potentiates tunicamycin-induced neuronal death in organotypic hippocampal slice cultures
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DOI：
10.1016/j.neuroscience.2007.04.057
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发表时间：
2007-07-13
期刊：
影响因子：
3.3
通讯作者：
Ito, Y.
中科院分区：
文献类型：
--
作者：
Imai, T.;Kosuge, Y.;Ito, Y.
我们在大鼠器官型海马切片培养物（OHC）中评估了淀粉样β蛋白（A β）诱导的神经毒性，加入和不加入衣霉素（TM），一种内质网（ER）中N-糖基化的抑制剂。在培养3周的大鼠OHC中，单独用A β（25-35）（25 μ M）处理48小时后几乎没有神经毒性。然而，单独使用TM，在20和80 μ g/mL之间的浓度下观察到浓度依赖性神经元死亡。当淀粉样β蛋白与衣霉素（A β +TM）组合时，细胞死亡比单独使用TM更严重。Western印迹分析显示，与单独暴露于TM相比，暴露于A β +TM后，钙蛋白酶活性以及caspase-12和caspase-3的活性形式增加。与此相反，葡萄糖调节蛋白（GRP）94，GRP 78和C/EBP同源蛋白（CHOP）的水平在A β的存在下没有改变。TM神经毒性的β增强作用被S-烯丙基-L-半胱氨酸（SAC）可逆地阻断，SAC是一种从老化大蒜提取物中纯化的有机硫化合物，L-型钙通道阻滞剂nifeclipine在OHC的受限神经元区域中。同时应用SAC还逆转了A β +TM引起的钙蛋白酶活性以及caspase-12和caspase-3活性形式的增加，而GRP 94、GRP 78和CHOP水平的增加没有变化。这些数据表明，AP促进钙蛋白酶-半胱天冬酶-12-半胱天冬酶-3途径，从而增强TM诱导的海马神经元死亡。(c)2007年IBRO。由爱思唯尔有限公司出版。保留所有权利。
We have assessed amyloid beta protein (A beta)-induced neurotoxicity, with and without added tunicamycin (TM), an inhibitor of N-glycosylation in the encloplasmic reticulum (ER), in rat organotypic hippocampal slice cultures (OHCs). In the rat OHCs cultured for 3 weeks, there was little neurotoxicity after treatment with A beta(25-35) (25 mu M) alone for 48 h. However, with TM alone, concentration-dependent neuronal death was observed at concentrations between 20 and 80 mu g/mL. When amyloid-beta protein was combined with tunicamycin (A beta+TM), cell death was more acute than with TM alone. Western blot analysis revealed that calpain activity and the active forms of caspase-12 and caspase-3 was increased after exposure to A beta+TM as compared with exposure to TM alone. In contrast, the levels of glucose regulated protein (GRP)94, GRP78 and C/EBP homologous protein (CHOP) were not changed in the presence of A beta. A beta potentiation of TM neurotoxicity was reversibly blocked by S-allyl-L-cysteine (SAC), an organosulfur compound purified from aged garlic extract, and the L-type calcium channel blocker, nifeclipine, in a restricted neuronal area of the OHCs. Simultaneously applied SAC also reversed the increases in calpain activity and the active forms of caspase-12 and caspase-3 by A beta+TM with no change in the increased levels of GRP94, GRP78 and CHOP. These data indicate that AP facilitates the calpain-caspase-12-caspase-3 pathway, thus potentiating TM-induced neuronal death in the hippocampus. (c) 2007 IBRO. Published by Elsevier Ltd. All rights reserved.