Bioresources and Environmental Biotechnology Laboratory, Department of Environmental Studies, University of Delhi, Delhi 110007, India.
Department of Botany, University of Pune, Pune 411007, Maharashtra, India.
J Ethnopharmacol. 2018 Jun 12;219:91-102. doi: 10.1016/j.jep.2018.03.005. Epub 2018 Mar 16.
Viscum articulatum Burm. f. (leafless mistletoe) has been used in traditional system of medicines in India, China, Taiwan, Cambodia, Laos, and Vietnam, to treat blood-related diseases and various inflammatory and degenerative diseases including cancer. Anticancer activities of some phytomolecules purified from Viscum articulatum Burm. f. have been tested. However scientific evidence for the anticancerous potential of aqueous extract of V. articularum (VAQE) used in traditional medicine is lacking.
To study the antiproliferative and apoptotic effect of VAQE on Jurkat E6.1 and THP1 leukemia cells.
The aqueous extract of the whole plant of Viscum articulatum Burm. f. was prepared in phosphate buffer saline. In VAQE, total soluble protein was estimated using Bradford's dye-binding assay; flavonoid content was determined using aluminum chloride colorimetric assay; and phenolic content was estimated following Folin-Ciocalteu colorimetric assay. XTT cell viability assay was used to test VAQE induced cytotoxicity in Jurkat E6.1 and THP1 leukemia cells and peripheral blood mononuclear cells (PBMC). The effect of VAQE on cell cycle progression was analyzed by PI staining using flow cytometry. Annexin-V-FITC/PI differential staining method was used for detecting the onset of apoptosis in leukemia cells. Rhodamine 123 dye was used to detect the change in mitochondrial membrane potential (MMP) using flow cytometry. DCF-DA fluorescence dye was used to estimate the level of reactive oxygen species (ROS). The ROS inhibitors were used to evaluate the role of ROS in mediating DNA degradation in VAQE-treated leukemia cells. The molecular mechanisms underlying VAQE induced apoptosis induction was studied by analyzing the expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) proteins, caspase-8 and caspase-3 enzymes using western blot. Diphenylamine (DPA) assay was used to determine the DNA fragmentation and conclusion of apoptosis.
VAQE triggered cytotoxic effect on Jurkat E6.1 (IC-2.4 µg/ml; 24 h) and THP1 (IC-1.0 µg/ml; 24 h) cells in a dose- and time-dependent manner. The apoptosis induction and G2/M arrest of the cell cycle are the cause of VAQE-induced cytotoxicity in leukemia cells. The apoptosis in VAQE-treated Jurkat E6.1 and THP1 cells was mediated via a reduction in MMP, elevation of intracellular ROS, decreased expression of the anti-apoptotic (Bcl-2) and increased expression of the pro-apoptotic (Bax) protein, activation of caspase-8 and caspase-3 and DNA fragmentation.
VAQE has a high efficacy to exert a cytotoxic effect in Jurkat E6.1 and THP1 cells and to induce apoptosis and G2/M cell cycle arrest. VAQE induces extrinsic pathway of apoptosis in both the leukemia cell lines via disruption of MMP, intracellular ROS imbalance, increased ratio of Bax/Bcl-2, activation of caspase-8, caspase-3 and ROS-mediated DNA fragmentation. The knowledge gained from the outcomes of the study may encourage the identification of novel chemotherapeutic agent from Viscum articulatum Burm. f. to treat leukemia.
Viscum articulatum Burm. f.（无叶槲寄生）在印度、中国、中国台湾、柬埔寨、老挝和越南的传统医学体系中被用于治疗与血液相关的疾病和各种炎症性及退行性疾病，包括癌症。一些从 Viscum articulatum Burm. f. 中纯化的植物分子的抗癌活性已被测试。然而，传统医学中使用的 V. articularum（VAQE）水提物的抗癌潜力缺乏科学证据。
研究 VAQE 对 Jurkat E6.1 和 THP1 白血病细胞的增殖抑制和凋亡作用。
用磷酸盐缓冲盐水制备 Viscum articulatum Burm. f. 全株植物的水提取物。在 VAQE 中，使用 Bradford 染色结合法估计总可溶性蛋白；使用铝氯化物比色法测定类黄酮含量；使用 Folin-Ciocalteu 比色法测定酚类含量。XTT 细胞活力测定法用于检测 VAQE 在 Jurkat E6.1 和 THP1 白血病细胞和外周血单核细胞（PBMC）中的细胞毒性。通过 PI 染色流式细胞术分析 VAQE 对细胞周期进程的影响。使用 Annexin-V-FITC/PI 差异染色法检测白血病细胞凋亡的发生。使用罗丹明 123 染料通过流式细胞术检测线粒体膜电位（MMP）的变化。使用 DCF-DA 荧光染料估计活性氧（ROS）的水平。使用 ROS 抑制剂评估 ROS 在介导 VAQE 处理的白血病细胞中 DNA 降解中的作用。通过分析抗凋亡（Bcl-2）和促凋亡（Bax）蛋白、半胱天冬酶-8 和半胱天冬酶-3 酶的表达，研究 VAQE 诱导凋亡的分子机制，使用 Western blot。使用二苯胺（DPA）测定法确定 DNA 片段化和凋亡的结论。
VAQE 以剂量和时间依赖的方式在 Jurkat E6.1（IC-2.4μg/ml；24 小时）和 THP1（IC-1.0μg/ml；24 小时）细胞中引发细胞毒性作用。细胞凋亡诱导和细胞周期 G2/M 期阻滞是 VAQE 诱导白血病细胞细胞毒性的原因。VAQE 处理的 Jurkat E6.1 和 THP1 细胞中的细胞凋亡是通过降低 MMP、增加细胞内 ROS、降低抗凋亡（Bcl-2）和增加促凋亡（Bax）蛋白表达、激活半胱天冬酶-8 和半胱天冬酶-3 以及 DNA 片段化来介导的。
VAQE 对 Jurkat E6.1 和 THP1 细胞具有高效的细胞毒性作用，并能诱导细胞凋亡和 G2/M 细胞周期阻滞。VAQE 通过破坏 MMP、细胞内 ROS 失衡、增加 Bax/Bcl-2 比值、激活半胱天冬酶-8、半胱天冬酶-3 和 ROS 介导的 DNA 片段化，在两种白血病细胞系中诱导细胞凋亡的外源性途径。从 Viscum articulatum Burm. f. 中识别新型化疗药物治疗白血病的研究结果可能会受到鼓励。
Zotero 插件