北豆根提取成分PE2诱导胃癌细胞凋亡的实验研究

Effect on Apoptosis of BGC823 Cells Induced by Rhizoma Menipermi Extracts-PE2

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。

BACKGROUND ＆ AIM： To study the effects of tumor cell apoptosis induced by Rhizoma Menipenni Extracts-PE2 and their mechanisms. MATERIAL AND METHODS： Rhizoma Menipenni extract with ethanol was preliminary purified using three steps method. PE2 was isolated and purified further by Pole Chromatogram. The apoptosis of tmnor ceils BGC823 induced by PE2 was studied by fluorescent staining, flow-cytometry （FCM）, electron microscopy and DNA agarose gel electrophoresis technique. RKSULTS： PE2 could induce apoptosis of BGC823 ceils in a dose-and time-dependent relationship. After treatment with PE2, the BGC823 cells received some typical morphologic features and super-microstructural changes ot 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 G0/G1 phase were observed. DNA agarose gel electrophoresis showed characteristic ＂ DNA ladder＂ pattern. After treatment with 5 μg/ml PE2, the ceils in G0/G1 phase were blocked and increased markedly. But the ceils in S phase were blocked after treatment with 50 μg/ml PE2. And the expression of bax was up-regulated. CONCLUSION：Rhizoma Menispenni Extract-PE2 induced 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.