Saleh Ayman M, Aljada Ahmad, Rizvi Syed A A, Nasr Amre, Alaskar Ahmed S, Williams Jack D
College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia.
BMC Complement Altern Med. 2014 Jul 7;14:226. doi: 10.1186/1472-6882-14-226.
The essential oil (EO) of Artemisia vulgaris L. has been traditionally used worldwide for treating a large number of diseases. Although major components in A. vulgaris EO have been shown to inhibit growth of different cancer cells, as pure compounds or part of other plants extracted oil, no information is known about its anti-proliferative activities. Therefore, the current investigation has evaluated the toxicity of the plant extracted oil from buds (AVO-b) and leaves (AVO-l) and characterized their growth inhibitory effects on cancer cells.
AVO-b and AVO-l from A. vulgaris L. were extracted by hydrodistillation, and their effect on the viability of human HL-60 promyelocytic leukemia and various other cancer cell lines was tested using MTT assay. Flow cytometric analysis of apoptosis, DNA fragmentation assay, caspases enzymatic activities and Western blotting were used to determine the apoptotic pathway triggered by their action on HL-60 cells.
Low concentrations of AVO-b and AVO-l inhibited the growth of HL-60 cells in a dose- and time-dependent manner. Employing flow cytometric, DNA fragmentation and caspase activation analyses, demonstrated that the cytotoxic effect of the oils is mediated by a caspase-dependent apoptosis. Kinetic studies in the presence and absence specific caspase inhibitors showed that activation of caspase-8 was dependent and subsequent to the activation of caspases-9 and -3. In addition, the essential oil caused a disruption of the mitochondrial transmembrane potential (ΔΨm), increased the release of cytochrome c to the cytosol, and altered the expression of certain members of Bcl-2 family (Bcl-2, Bax and Bid), Apaf-1 and XIAP. Interestingly, low doses of AVO-b and AVO-1 also induced apoptosis in various cancer cell lines, but not in noncancerous cells.
The results demonstrate that the EO-induced apoptosis in HL-60 cells is mediated by caspase-dependent pathways, involving caspases-3, -9, and -8, which are initiated by Bcl-2/Bax/Bid-dependent loss of ΔΨm leading to release of cytochrome c to the cytoplasm to activate the caspase cascade. The finding that AVO-b and AVO-l are more efficient to induce apoptosis in different cancer cell lines than noncancerous cells, suggests that A. vulgaris might be a promising source for new anticancer agents.
普通艾草的精油在世界各地传统上被用于治疗多种疾病。尽管普通艾草精油中的主要成分已被证明可抑制不同癌细胞的生长，无论是作为纯化合物还是其他植物提取物油的一部分，但其抗增殖活性尚无相关信息。因此，本研究评估了从芽（AVO-b）和叶（AVO-l）中提取的植物精油的毒性，并表征了它们对癌细胞的生长抑制作用。
通过水蒸馏法提取普通艾草的AVO-b和AVO-l，并使用MTT法检测它们对人HL-60早幼粒细胞白血病细胞和其他多种癌细胞系活力的影响。采用流式细胞术分析凋亡、DNA片段化检测、半胱天冬酶酶活性检测和蛋白质印迹法来确定它们对HL-60细胞作用所触发的凋亡途径。
低浓度的AVO-b和AVO-l以剂量和时间依赖性方式抑制HL-60细胞的生长。通过流式细胞术、DNA片段化和半胱天冬酶激活分析表明，这些精油的细胞毒性作用是由半胱天冬酶依赖性凋亡介导的。在存在和不存在特异性半胱天冬酶抑制剂的情况下进行的动力学研究表明，半胱天冬酶-8的激活依赖于半胱天冬酶-9和-3的激活且在其之后。此外，精油导致线粒体跨膜电位（ΔΨm）的破坏，增加细胞色素c向细胞质的释放，并改变Bcl-2家族某些成员（Bcl-2、Bax和Bid）、凋亡蛋白酶激活因子-1（Apaf-1）和X连锁凋亡抑制蛋白（XIAP）的表达。有趣的是，低剂量的AVO-b和AVO-1也能诱导多种癌细胞系凋亡，但对非癌细胞无此作用。
结果表明，精油诱导HL-60细胞凋亡是由半胱天冬酶依赖性途径介导的，涉及半胱天冬酶-3、-9和-8，这些途径由Bcl-2/Bax/Bid依赖性的ΔΨm丧失引发，导致细胞色素c释放到细胞质中以激活半胱天冬酶级联反应。AVO-b和AVO-l在不同癌细胞系中比在非癌细胞中更有效地诱导凋亡这一发现表明，普通艾草可能是新抗癌药物的一个有前景的来源。
