雷公藤红素通过活性氧诱导结肠癌SW620细胞凋亡

Celastrol induces apoptosis in human colon cancer SW620 cells through species reactive oxygen

目的:探讨雷公藤红素(celestrol)诱导KRAS驱动的结肠癌SW620细胞产生凋亡的作用和机制。方法:四甲基偶氮唑蓝(MTT)法和台盼蓝拒染法检测细胞增殖;免疫印迹法检测蛋白表达;流式细胞仪和荧光显微镜检测细胞凋亡、细胞周期、线粒体膜电位;荧光显微镜检测细胞内活性氧水平(reactive oxygen species,ROS)。结果:雷公藤红素明显抑制SW620细胞的增殖活性;雷公藤红素下调SW620胞内的p-Akt、NF-κB、Survivin表达,激活caspase-7、caspase-3和PARP;雷公藤红素增加SW620细胞内的ROS、降低线粒体膜电位、阻滞细胞周期于G2/M期和诱导凋亡。抗氧化剂N-乙酰半胱氨酸(NAC)抑制雷公藤红素引起的上述作用。结论:通过诱导细胞内ROS的累积导致细胞内线粒体膜电位的下降进而触发细胞发生凋亡是雷公藤红素诱导SW620细胞凋亡的作用机制之一。

OBJECTIVE To investigate effects of celastrol induced apoptosis and its mechanism on human colon cancer SW620 cells.METHODS Proliferation was detected by MTT or typlan blue exclusion staining method.Expression of proteins was detected by Western blot.Cell cycle,mitochondrial membrane potential and apoptosis were measured by flow cytometry.ROS was detected by microscopy.RESULTS Celastrol inhibited proliferation of SW620 cells;celastrol down-regulated expression of p-Akt,NF-κB,Survivin and activated caspase 7,caspase 3 and PARP;celastrol induced ROS accumulation,apoptosis,depolarization of mitochondrial membrane and arrested cell cycle at G2/M in SW620 cells.However,these effects of celastrol could be inhibited by NAC.CONCLUSION Mitochondrial membrane is depolarized by accumulation of intracellular ROS,and thus apoptosis is trigged which may be one of mechanisms for celastrol to induce apoptosis in SW620 cells.