Laboratory of Experimental Biochemistry, Scientific Institute for Digestive Diseases, IRCCS Saverio de Bellis, I-70013 Castellana G, BA, Italy.
Anticancer Res. 2010 Sep;30(9):3501-7.
BACKGROUND/AIM: Polyamines and ornithine decarboxylase are involved in cell growth and differentiation. The polyphenol quercetin may exert anti-tumour properties by influencing proliferation, differentiation, and apoptosis. The aim of the study was to investigate the effects of increasing concentrations of quercetin (from 0.1 to 100 μM) on polyamine biosynthesis, cell proliferation, and apoptosis in the DLD-1 cells.
Polyamine levels and ornithine decarboxylase activity were evaluated by HPLC and radiometric technique, respectively. The proliferative response was estimated by 3-(4,5 dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide (MTT) test and [(3)H]-thymidine incorporation in cell DNA. Apoptosis was investigated by DNA fragmentation.
At concentrations ≥50 μM, quercetin significantly reduced ornithine decarboxylase activity, putrescine and spermidine levels compared to controls and cells treated with 0.1 μM concentration. Quercetin concentrations ≥70 μM caused a significant reduction in the conversion of MTT tetrazolium salt and [(3)H]-thymidine incorporation. The same concentrations were needed to induce the apoptosis.
The present study demonstrates that quercetin can affect growth of DLD-1 cells by both decreasing polyamine biosynthesis and inducing apoptosis. Due to the extensive dietary consumption of polyphenols, such as quercetin, the biological activity of these compounds deserves further investigation.
背景/目的：多胺和鸟氨酸脱羧酶参与细胞生长和分化。多酚槲皮素可能通过影响增殖、分化和凋亡来发挥抗肿瘤特性。本研究的目的是研究增加槲皮素浓度（从 0.1 到 100 μM）对 DLD-1 细胞中多胺生物合成、细胞增殖和细胞凋亡的影响。
通过 HPLC 和放射性技术分别评估多胺水平和鸟氨酸脱羧酶活性。通过 3-(4,5 二甲基噻唑-2-基)-2,5-二苯基四氮唑溴化物（MTT）试验和细胞 DNA 中[(3)H]-胸苷掺入来估计增殖反应。通过 DNA 片段化研究凋亡。
在浓度≥50 μM 时，与对照组和用 0.1 μM 浓度处理的细胞相比，槲皮素显著降低了鸟氨酸脱羧酶活性、腐胺和亚精胺水平。浓度≥70 μM 的槲皮素会导致 MTT 四唑盐的转化和[(3)H]-胸苷掺入显著减少。同样的浓度需要诱导细胞凋亡。
本研究表明，槲皮素可以通过降低多胺生物合成和诱导细胞凋亡来影响 DLD-1 细胞的生长。由于多酚类化合物（如槲皮素）的广泛饮食摄入，这些化合物的生物学活性值得进一步研究。
