人参皂苷 Re 和 Rg3 对 C6 神经胶质瘤细胞内氧化还原状态和细胞增殖的影响。

BACKGROUND

Cellular redox state is important to cell growth and death. The growth of tumor cells may be modulated by intracellular reduced glutathione/oxidized glutathione (GSH/GSSG). The present study aims to investigate the effects of ginsenosides Re and Rg3 on cellular redox state and cell proliferation in C6 glioma cells.

METHODS

Cultured C6 glioma cells were exposed to various concentrations of either Rg3 or Re for 24 hours. Cell growth and death were measured by the BrdU incorporation assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay respectively. Cellular redox state was determined by free radical production using flow cytometry and GSH/GSSG using spectrofluorometry.

RESULTS

At a sub-lethal concentration, Re suppressed cell proliferation with a significant decrease in BrdU incorporation. Re did not increase reactive oxygen species (ROS) production but increased GSH/GSSG via increased activity of gamma glutamylcystenyl synthase (gamma-GCS). In contrast, Rg3 increased free radical production and reduced GSH/GSSG. The effects of Rg3 were probably due to increased activity of glutathione peroxidase (GPx).

CONCLUSION

Re and Rg3 alter cellular redox state of C6 glioma cells in opposite directions. Changes in cellular redox state induced by Re and Rg3 are correlated with the proliferation rates of C6 glioma cells.

背景

细胞的氧化还原状态对细胞的生长和死亡很重要。肿瘤细胞的生长可能受到细胞内还原型谷胱甘肽/氧化型谷胱甘肽（GSH/GSSG）的调节。本研究旨在探讨人参皂苷 Re 和 Rg3 对 C6 神经胶质瘤细胞内氧化还原状态和细胞增殖的影响。

方法

培养的 C6 神经胶质瘤细胞分别暴露于不同浓度的 Rg3 或 Re 24 小时。通过 BrdU 掺入测定和 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）测定分别测量细胞生长和死亡。通过使用流式细胞术测定自由基产生和使用分光荧光法测定 GSH/GSSG 来确定细胞氧化还原状态。

结果

在亚致死浓度下，Re 抑制细胞增殖，BrdU 掺入显著减少。Re 没有增加活性氧（ROS）的产生，但通过增加γ-谷氨酰半胱氨酸合成酶（γ-GCS）的活性增加了 GSH/GSSG。相比之下，Rg3 增加了自由基的产生并减少了 GSH/GSSG。Rg3 的作用可能是由于谷胱甘肽过氧化物酶（GPx）活性的增加。