A novel polycyclic bridged-ring xanthene 2 was synthesized by nucleophilic substitution followed by Michael addition reaction between parent dibenzoxanthene 1 and acetylacetone. The structure of compound 2 was also confirmed by single-crystal X-ray diffraction. We studied the binding activity of this compound with bovine serum albumin (BSA) by fluorescent and UV–visible spectra. The results showed that compound had strong binding ability with BSA. Cell viability in five tumor cell lines was studied by MTT assay. The cytotoxic effect of bridged-ring xanthene 2 against BEL-7402 cells was examined by morphological analyses and biochemical assays. Significant nuclear damages of BEL-7402 cells were observed after cells were treated with compound in a comet assay. The compound also caused DNA damage and S phase arrest in BEL-7402 cells. The efficient induction of apoptosis by the compound was confirmed by flow cytometry. Additionally, the characteristic nuclear and morphological changes during apoptotic cell death were investigated by fluorescent microscopy. The compound 2 enhanced the reactive oxygen species (ROS) and decreased the mitochondrial membrane potential. Western blot assay indicated that the compound can active caspase-3, caspase-7, down-regulate the level of Bcl-2, Bcl-x, and up-regulate the level of pro-apoptosis protein Bax. The compound 2 induces apoptosis of BEL-7402 cells through a ROS-mediated mitochondrial dysfunction pathway.
通过母体二苯并
氧杂蒽 1 与
乙酰丙酮之间的亲核取代和迈克尔加成反应,合成了一种新型多环桥环
氧杂蒽 2。化合物 2 的结构也通过单晶 X 射线衍射得到了证实。我们通过荧光光谱和紫外可见光谱研究了该化合物与
牛血清白蛋白(
BSA)的结合活性。结果表明,该化合物与
BSA 有很强的结合能力。通过 M
TT 试验研究了五种肿瘤
细胞系的细胞活力。通过形态学分析和生化试验研究了桥环呫吨 2 对 BEL-7402 细胞的细胞毒性作用。在彗星试验中,用化合物处理 BEL-7402 细胞后,观察到细胞核明显受损。该化合物还导致了 BEL-7402 细胞的 DNA 损伤和 S 期停滞。流式细胞术证实了该化合物能有效诱导细胞凋亡。此外,荧光显微镜还研究了细胞凋亡过程中细胞核和形态的特征性变化。化合物 2 增加了活性氧(ROS),降低了线粒体膜电位。Western 印迹分析表明,该化合物能激活 caspase-3、caspase-7,下调 Bcl-2、Bcl-x 的
水平,上调促凋亡蛋白 Bax 的
水平。化合物 2 通过 ROS 介导的线粒体功能障碍途径诱导 BEL-7402 细胞凋亡。