【摘要】 背景与目的:探讨北豆根有效成分诱导肿瘤细胞凋亡的作用及其作用机制。材料与方法:北豆根干品醇提液,经三步法将醇提液纯化,得到三种纯化提取物(Purifiedextract,PE)PE1、2、3。应用流式细胞技术分析细胞周期DNA变化,并经荧光染色和荧光显微镜观察凋亡细胞形态学变化。并用电子显微镜观察了凋亡细胞的超微结构变化。用凝胶电泳实验检测了凋亡细胞DNA变化。结果:PE2可诱导BGC823细胞凋亡,呈明显的时效和量效关系;在低浓度PE2作用下,多数细胞被阻滞在G0/G1期,高浓度PE2作用后,多数细胞被阻滞在S期。肿瘤细胞经PE2作用后发生细胞凋亡的形态学变化:体积缩小,胞质浓缩,出现核固缩、核碎裂等;在电子显微镜下可见细胞胞体缩小,核染色质高度浓缩,边集于核膜,有的呈半月形,有的出现核碎裂,偶见凋亡小体。细胞DNA经凝胶电泳后,出现典型的梯状电泳模式。PE2处理的癌细胞,bcl-2基因表达降低,而bax基因表达升高。结论:PE2诱导肿瘤细胞凋亡,通过调节bcl-2及bax基因的表达发挥作用是PE2抗肿瘤作用的机制之一。该结果可促进北豆根的二次开发和临床应用。更多还原

【Abstract】 BACKGROUND&AIM: To study the effects of tumor cell apoptosis induced by Rhizoma Menipermi Extracts_PE2and their mechanisms. MATERIAL AND METHODS: Rhizoma Menipermi extract with ethanol was preliminary purified using three steps method.PE2was isolated and purified further by Pole Chromatogram.The apoptosis of tumor cells BGC823induced by PE2was studied by fluorescent staining,flow_cytometry(FCM),electron microscopy and DNA agarose gel electrophoresis technique. RESULTS: PE2could induce apoptosis of BGC823cells in a dose_and time_dependent relationship.After treatment with PE2,the BGC823cells received some typical morphologic features and super_microstructural changes of apoptosis,including cell shrinkage chromatin concentrating on nuclear membrane or forming crescent,nuclear condensation,nuclear fragmentation and formation of apoptotic bodies.Some typical subdiploid peaks before G 0 /G 1 phase were observed.DNA agarose gel electrophoresis showed characteristic”DNA ladder”pattern.After treatment with5μg/ml PE2,the cells in G 0 /G 1 phase were blocked and increased markedly.But the cells in S phase were blocked after treatment with50μg/ml PE2.And the expression of bax was up_regulated. CONCLUSION: Rhizoma Menispermi Extract_PE2induced tumor cell apoptosis,which was an important mechanism of its anti_tumor effect.Futher purification and study of their mechanisms can produce the scientific evidence for developing and manufacturing new antitumor drugs.更多还原