缺血后处理通过上调磷酸化丝氨酸/苏氨酸蛋白激酶阻断细胞色素C释放保护缺血性神经元损伤

张立柱 周彩凤 涂静宜 张茜 朱莹 王瑞敏1*

doi:10.3969/j.issn.0529-1356.2013.02.002

解剖学报 ›› 2013, Vol. 44 ›› Issue (2) : 152-156. DOI: 10.3969/j.issn.0529-1356.2013.02.002

神经生物学

缺血后处理通过上调磷酸化丝氨酸/苏氨酸蛋白激酶阻断细胞色素C释放保护缺血性神经元损伤

张立柱^1,2 周彩凤^1,3 涂静宜¹ 张茜¹ 朱莹¹ 王瑞敏^1*

作者信息 +

Ischemic postconditioning prevents cytochrome C release through up-regulation of p-Akt and protects neurons against ischemia insult 

ZHANG Li-zhu ^1,2 ZHOU Cai-feng ^1,3 TU Jing-yi¹ ZHANG Xi¹ ZHU Ying¹ WANG Rui-min^1*

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文章历史 +

摘要

目的通过观察脑缺血再灌注大鼠海马CA1区神经元内丝氨酸/苏氨酸蛋白激酶B（Akt）及细胞色素C 的表达及定位情况，探讨延迟性脑缺血后处理神经保护作用及其可能的分子机制。方法制作SPF级成年雄性SD大鼠（40只）四动脉结扎全脑缺血模型。实验动物随机分为假手术组，缺血再灌注组，后处理组，抑制剂组及溶剂对照组。采用焦油紫染色技术观察大鼠海马CA1区神经元存活情况；Western blotting法检测磷酸化Akt及细胞色素C的表达及定位。结果延迟性的脑缺血后处理能够促进缺血再灌注大鼠海马CA1区神经元生存；促进磷酸化Akt水平升高；阻止线粒体内细胞色素C向胞质释放；脑室注射LY294002后，细胞色素C的释放减少，抑制延迟性后处理的神经元保护作用。结论延迟性脑缺血后处理通过诱导胞质内Akt的磷酸化，抑制线粒体内细胞色素C释放到胞质，阻止全脑缺血再灌注后大鼠海马CA1区神经元损伤。

Abstract

Objective The goal of this study is to elucidate the neuro-protective effect and the possible mechanism of delayed ischemic postconditioning through observing the level of p-Akt and cytochrome C (Cyt C) in cytoplasm or mitochondria following global cerebral ischemia. Methods 40 Adult male Sprague-Dawley rats were subjected to global cerebral ischemia by four-vessel occlusion and were randomly divided into five groups: sham group, ischemia-reperfusion group (I/R), delayed ischemic postconditioning group (Post C), Vehicle group (Post C+Vehicle) and LY294002 group (Post C+LY294002). Cresyl violet staining was used to observe the surviving neurons of hippocampal CA1 region following global cerebral ischemia and western blot analysis was used to detect the level of p-Akt and Cyt C in both cytosolic and mitochondrial fraction. Results Delayed ischemic postconditioning protected the hippocampal CA1 region neurons against ischemia/referfusion injury and significantly increased the level of p-Akt in cytoplasm compared with I/R groups. Delayed ischemic postconditioning markedly prevented the release of Cyt C from mitochondria to cytoplasm and LY294002, an inhibitor of Akt up-stream kinase, abolished the positive role of delayed ischemic postconditioning. Conclusion Delayed ischemic postconditioning induces the Akt activation and prevents the release of Cyt C from mitochondria to cytoplasm, thereby blocks the hippocampal CA1 region neurons injury following global cerebral ischemia.

导出引用

张立柱周彩凤涂静宜张茜朱莹王瑞敏1*. 缺血后处理通过上调磷酸化丝氨酸/苏氨酸蛋白激酶阻断细胞色素C释放保护缺血性神经元损伤[J]. 解剖学报. 2013, 44(2): 152-156 https://doi.org/10.3969/j.issn.0529-1356.2013.02.002

ZHANG Li-zhu ZHOU Cai-feng TU Jing-yi ZHANG Xi ZHU Ying WANG Rui-min* . Ischemic postconditioning prevents cytochrome C release through up-regulation of p-Akt and protects neurons against ischemia insult [J]. Acta Anatomica Sinica. 2013, 44(2): 152-156 https://doi.org/10.3969/j.issn.0529-1356.2013.02.002

中图分类号： R363.2

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