BH3-mimetic ABT-737 induces strong mitochondrial membrane depolarization in platelets but only weakly stimulates apoptotic morphological changes, platelet shrinkage and microparticle formation
BH3-mimetic ABT-737 induces strong mitochondrial membrane depolarization in platelets but only weakly stimulates apoptotic morphological changes, platelet shrinkage and microparticle formation
复制标题
DOI：
10.1016/j.thromres.2013.10.041
复制
发表时间：
2014-01-01
影响因子：
7.5
通讯作者：
Leytin, Valery
中科院分区：
文献类型：
--
作者：
Gyulkhandanyan, Armen V.;Mutlu, Asuman;Leytin, Valery
背景：线粒体内跨膜电位的去极化(Delta Psi M)是无核血小板内源性细胞凋亡途径的重要生化表现。目的：阐明人血小板中的这种关系。材料与方法：利用流式细胞术，我们分析了BH3模拟物ABT-737和钙离子载体A23187处理的血小板的Delta psim去极化、血小板收缩和MP形成。结果：我们发现在最佳处理条件下(90min，37℃)，ABT-737和A23187都能诱导大多数(88-94%)血小板的Delta psim去极化，并显著增加细胞内游离钙。相反，A23187和ABT-737对血小板收缩和MP形成的影响是完全不同的。A23187强烈刺激细胞收缩和MP的形成，而ABT737仅微弱地诱导这些事件(作用是A23187的10-20%，P<；0.0001)。结论：这些数据表明，高水平的Delta psim去极化和细胞内游离钙并不一定能确保强烈的血小板收缩和MP的形成。由于ABT-737可以有效地诱导血小板从循环中清除，我们的结果表明，在没有细胞凋亡的形态表现的情况下，可能会发生血小板清除。皇冠版权所有(C)2013由爱思唯尔有限公司出版。保留所有权利。
Background: Depolarization of mitochondrial inner transmembrane potential (Delta psi m) is a key biochemical manifestation of the intrinsic apoptosis pathway in anucleate platelets. Little is known, however, about the relationship between Delta psi m depolarization and downstream morphological manifestations of platelet apoptosis, cell shrinkage and microparticle (MP) formation.Objectives: To elucidate this relationship in human platelets.Materials and Methods: Using flow cytometry, we analyzed Delta psi m depolarization, platelet shrinkage and MP formation in platelets treated with BH3-mimetic ABT-737 and calcium ionophore A23187, well-known inducers of intrinsic platelet apoptosis.Results: We found that at optimal treatment conditions (90 min, 37 degrees C) both ABT-737 and A23187 induce Delta psi m depolarization in the majority (88-94%) of platelets and strongly increase intracellular free calcium. In contrast, effects of A23187 and ABT-737 on platelet shrinkage and MP formation are quite different. A23187 strongly stimulates cell shrinkage and MP formation, whereas ABT-737 only weakly induces these events (10-20% of the effect seen with A23187, P < 0.0001).Conclusions: These data indicate that a high level of Delta psi m depolarization and intracellular free calcium does not obligatorily ensure strong platelet shrinkage and MP formation. Since ABT-737 efficiently induces clearance of platelets from the circulation, our results suggest that platelet clearance may occur in the absence of the morphological manifestations of apoptosis. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.