Unami Akira, Shinohara Yasuo, Ichikawa Tomokazu, Baba Yoshinobu
Faculty of Pharmaceutical Sciences, University of Tokushima, 1 Shomachi, Tokushima 770-8505, Japan.
J Toxicol Sci. 2003 May;28(2):77-94. doi: 10.2131/jts.28.77.
The mechanism by which apoptosis is induced by local anesthetic bupivacaine, a potent uncoupler of mitochondrial oxidative phosphorylation, was investigated. In promyelocytic leukemia cells HL-60, bupivacaine induced formation of apoptotic bodies and DNA fragmentation in a time- and dose-dependent manner similar to typical apoptosis inducers. Caspase-3, -8 and -9, which play a pivotal role in the initiation and execution of receptor- or mitochondria-mediated apoptosis, were all clearly activated by bupivacaine in good correlation with the degree of DNA fragmentation. However, bupivacaine did not induce either mitochondrial permeability transition (PT) or release of cytochrome c in experiments with isolated mitochondria. These results suggest that an indirect action of bupivacaine on mitochondria occurs and that other mechanisms may be involved in bupivacaine-induced apoptosis. To obtain additional information concerning the mechanism of action involved in bupivacaine-induced apoptosis, a microarray analysis of gene expression in bupivacaine-treated HL-60 cells was carried out. Several apoptosis-related genes were found to be transcriptionally regulated by bupivacaine using a high-density cDNA microarray. The expression levels of heat shock protein 70 (HSP70), c-jun and c-fos genes were remarkably up-regulated and those of c-myc and poly (ADP ribose) polymerase (PARP) were down-regulated in bupivacaine-treated cells. These results are of value in developing a better understanding of the molecular mechanism of bupivacaine-induced apoptosis leading to neuro- or myotoxicity.
研究了局部麻醉药布比卡因（一种强效的线粒体氧化磷酸化解偶联剂）诱导细胞凋亡的机制。在早幼粒细胞白血病细胞HL-60中，布比卡因以时间和剂量依赖性方式诱导凋亡小体形成和DNA片段化，类似于典型的凋亡诱导剂。在受体或线粒体介导的凋亡起始和执行中起关键作用的半胱天冬酶-3、-8和-9均被布比卡因明显激活，且与DNA片段化程度密切相关。然而，在分离线粒体的实验中，布比卡因未诱导线粒体通透性转换（PT）或细胞色素c释放。这些结果表明布比卡因对线粒体存在间接作用，且其他机制可能参与布比卡因诱导的细胞凋亡。为了获取有关布比卡因诱导细胞凋亡作用机制的更多信息，对布比卡因处理的HL-60细胞进行了基因表达微阵列分析。使用高密度cDNA微阵列发现几种凋亡相关基因受布比卡因转录调控。在布比卡因处理的细胞中，热休克蛋白70（HSP70）、c-jun和c-fos基因的表达水平显著上调，而c-myc和聚（ADP核糖）聚合酶（PARP）的表达水平下调。这些结果对于更好地理解布比卡因诱导细胞凋亡导致神经或肌肉毒性的分子机制具有重要价值。
