Comparative cytotoxicity and ROS generation by curcumin and tetrahydrocurcumin following visible-light irradiation or treatment with horseradish peroxidase.
Comparative cytotoxicity and ROS generation by curcumin and tetrahydrocurcumin following visible-light irradiation or treatment with horseradish peroxidase.
复制标题
可见光照射或辣根过氧化物酶处理后姜黄素和四氢姜黄素的细胞毒性和 ROS 生成的比较。
作者：
T. Atsumi;K. Tonosaki;S. Fujisawa
为了阐明众所周知的化学预防剂姜黄素的细胞毒性机制，在两种不同的氧化条件下，测量了姜黄素和四氢姜黄素 (TH-curcumin) 处理的癌症 (HSG) 和正常 (HGF) 细胞的细胞毒性（通过 MTT 法）、细胞内谷胱甘肽（使用 GSH 检测试剂盒）和细胞内活性氧 (ROS) 水平（使用流式细胞仪）：光 (VL) 和辣根过氧化物酶 (HRP)/H2O2 的酶促氧化。 VL 照射大大增强了姜黄素的细胞毒性，而 HRP/H2O2 处理则增强了 TH-姜黄素的细胞毒性。姜黄素对HGF细胞的细胞毒性大于对HSG细胞的细胞毒性。姜黄素在 VL 照射下显着降低细胞内 GSH 水平，并在 HRP/H2O2 下增加细胞内 GSH 水平，而 TH-姜黄素对任一氧化处理均没有影响。 TH-姜黄素的HRP/H2O2处理增强ROS的产生；相反，姜黄素的VL照射被认为能更好地产生ROS。总之，姜黄素具有高度光毒性，导致 GSH 减少并介导 ROS 生成。相反，TH-姜黄素的细胞毒性通过酶促氧化而增强。 TH-姜黄素诱导的低水平促氧化剂细胞内环境可有效预防癌症。
In order to clarify the cytotoxic mechanism of curcumin, a well-known chemopreventive agent, the cytotoxicity (by MTT method), intracellular glutathione (using GSH detection kit) and intracellular reactive oxygen species (ROS) levels (with a flow cytometer), were measured in curcumin- and tetrahydrocurcumin (TH-curcumin)-treated cancer (HSG) and normal (HGF) cells under two different oxidation conditions: irradiation with visible light (VL) and enzymatic oxidation with horseradish peroxidase (HRP)/H2O2. The cytotoxicity of curcumin was highly enhanced by VL-irradiation, whereas that of TH-curcumin was enhanced by HRP/H2O2 treatment. The cytotoxicity of curcumin against HGF cells was greater than that against HSG cells. Curcumin significantly reduced the intracellular GSH level significantly under VL-irradiation, and increased it under HRP/H2O2, whereas TH-curcumin had no effect with either oxidation treatment. HRP/H2O2 treatment of TH-curcumin enhanced generation of ROS; in contrast, VL-irradiation of curcumin was considered to produce ROS preferably. In conclusion, curcumin was highly photo-toxic, caused a decrease in GSH and mediated ROS generation. In contrast, the cytotoxicity of TH-curcumin was enhanced by enzymatic oxidation. A low-level pro-oxidant intracellular milieu induced by TH-curcumin could be effectively useful for cancer prevention.