Ito C, Itoigawa M, Nakao K, Murata T, Tsuboi M, Kaneda N, Furukawa H
Department of Medicinal Chemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan.
Phytomedicine. 2006 May;13(5):359-65. doi: 10.1016/j.phymed.2005.03.010. Epub 2005 Sep 15.
In the current study, we isolated 10 carbazole alkaloids from the plant species Murraya koenigii (Rutaceae), and examined their effects on the growth of the human leukemia cell line HL-60. Three carbazole alkaloids, mahanine (6), pyrayafoline-D (7) and murrafoline-I (9), showed significant cytotoxicity against HL-60 cells. Fluorescence microscopy with Hoechst 33342 staining revealed that the percentage of apoptotic cells with fragmented nuclei and condensed chromatin was increased in a time-dependent manner after treatment with each alkaloid. Interestingly, each carbazole alkaloid induced the loss of mitochondrial membrane potential. In addition, both caspase-9 and caspase-3 were also time-dependently activated upon treatment with the alkaloids. Caspase-9 and caspase-3 inhibitors suppressed apoptosis induced by these alkaloids. The results suggest that these three alkaloids induced apoptosis in HL-60 cells through activation of the caspase-9/caspase-3 pathway, through mitochondrial dysfunction.
在本研究中，我们从植物物种九里香（芸香科）中分离出10种咔唑生物碱，并检测了它们对人白血病细胞系HL-60生长的影响。三种咔唑生物碱，马汉宁（6）、吡雷亚福林-D（7）和九里香素-I（9），对HL-60细胞显示出显著的细胞毒性。用Hoechst 33342染色的荧光显微镜检查显示，用每种生物碱处理后，核碎片化和染色质浓缩的凋亡细胞百分比呈时间依赖性增加。有趣的是，每种咔唑生物碱均诱导线粒体膜电位丧失。此外，用生物碱处理后，半胱天冬酶-9和半胱天冬酶-3也呈时间依赖性激活。半胱天冬酶-9和半胱天冬酶-3抑制剂抑制了这些生物碱诱导的细胞凋亡。结果表明，这三种生物碱通过线粒体功能障碍激活半胱天冬酶-9/半胱天冬酶-3途径，从而诱导HL-60细胞凋亡。
