魔芋葡甘聚糖对人结肠细胞株基因组稳定性的影响

Effects of Konjac Glucomannan on Genome Stability of Human Colon Cell Lines

摘要:

为探究魔芋葡甘聚糖（Konjac gluconnan，KGM）对结肠上皮细胞基因组稳定性的影响，以正常结肠细胞株NCM460和结肠癌细胞株SW620、HCT116为研究材料，用质量浓度为0、0.625、1.25、2.5、5、10、20、40 mg/mL的KGM处理受试细胞24、48、72 h，以四氮唑蓝（MTT）法检测细胞活力；并以CBMN-Cyt实验检测质量浓度分别为5、20、30 mg/mL的KGM处理72 h后受试细胞的基因组不稳定性（Genome instability，GIN）、核分裂指数（nuclear division index，NDI）及凋亡水平。结果显示，不同质量浓度KGM作用72 h后，在5~40 mg/mL 范围内NCM460细胞活力显著上升（P<0.05），其GIN在KGM质量浓度为5 mg/mL时极显著降低（P<0.001），而30 mg/mL时则极显著升高（P<0.01）；5~40 mg/mL 的KGM显著抑制HCT116细胞的活力（PP<0.05），在40 mg/mL时SW620细胞活力极显著被抑制（P<0.01），且在KGM质量浓度为5~30 mg/mL时，SW620和HCT116这2株细胞的GIN和细胞凋亡率均显著增加（P<0.001），NDI显著降低（P<0.05）。结果表明，低质量浓度（5 mg/mL）的KGM有利于维护正常结肠上皮细胞NCM460的基因组稳定性，各质量浓度（5~30 mg/mL）的KGM都会增加结肠癌细胞SW620和HCT116 GIN的凋亡发生率，这可能是其维护肠道健康的分子基础。

Abstract:

To explore the effect of konjac glucomannan (KGM) on genomic stability in colonic epithelial cells, the normal colon cell line NCM460 and the colonic cancer cell lines SW620 and HCT116 were used as the research materials. The tested cells were treated with KGM at concentrations of 0, 0.625, 0.625, 2.5,5, 10, 20, and 40 mg/mL for 24, 48, and 72 h. Cell viability was detected by methylthiazolyldiphenyl-tetrazolium bromide(MTT) assay. The CBMN-Cyt assay was performed to detect the genome instability (GIN), nuclear division index (NDI), and apoptosis levels in the tested cells after treatment with different concentrations of KGM (5, 20, and 30 mg/mL) for 72 h. The results showed that after 72 h of treatment with different concentrations of KGM, the viability of NCM460 cells increased significantly(P<0.05) within 5~40 mg/mL, while their GIN significantly decreased(P<0.001) at 5 mg/mL KGM and significantly increased at 30 mg/mL(P<0.01). The viability of HCT116 cells was significantly inhibited by KGM at concentrations of 5~40 mg/mL (P<0.05), while KGM at a concentration of 40 mg/mL exhibited an extremely pronounced inhibitory effect on the viability of SW620 cells(P<0.01). Moreover, GIN and apoptosis rate of SW620 and HCT11 cells significantly increased at KGM concentrations of 5~30 mg/mL(P<0.001), while NDI reduced significantly(P<0.05). The results suggest that low concentration(5 mg/mL) of KGM is beneficial to maintain the genomic stability in normal epithelial cell NCM460, and various concentrations(5~30 mg/mL) of KGM increases GIN and apoptosis rate in the colon cancer cells SW620 and HCT116, which may provide a molecular basis for maintaining intestinal health.