Unidad de Experimentación Animal, Facultad de Química, Universidad Nacional Autónoma de México, Z.P. 04510 Mexico City, Mexico; Laboratorio de Farmacología, Instituto Nacional de Pediatría, SSA Mexico City Z.P. 04530, Mexico.
Toxicol In Vitro. 2011 Jun;25(4):868-73. doi: 10.1016/j.tiv.2011.02.007. Epub 2011 Feb 24.
Casiopeína IIgly (Cas IIgly) [Cu(4,7-dimethyl-1,10-phenanthroline)(glycinate)]NO(3) induce oxidative damage in different human tumour cell strains, as the known anticancer agent cisplatin (CDDP) does.
To compare glutathione (GSH) depletion induced by Cas IIgly and CDDP in murine melanoma B16 cells and its relationship with their antiproliferative effect.
Cell growth was determined according to the sulforhodamine B assay. Intracellular GSH levels were measured by the reduction of Ellman's reagent (DTNB).
Cas IIgly IC50 in B16 cells was 54.5 μM (24.21 μg/mL), which depleted GSH from 1092 to 585 ng per million cells in a 30 min incubation period. In the other hand, CDDP was less toxic at the same conditions with an IC50 equal to 197.76 μM (59.33 μg/mL), and depleted GSH to 50% of the normal only after a longer exposure period (4h). The addition of 1.8mM ascorbic acid (Asc) or 1mM buthionine sulfoximine (BSO) enhanced Cas IIgly toxicity, whereas it was prevented by 100 U/mL catalase. BSO sensitised B16 cells to CDDP, but neither Asc or catalase modified CDDP effects.
The antiproliferative effect of both drugs correlated to intracellular GSH levels. Unlike CDDP, GSH depletion induced by Cas IIgly occurs earlier, it is enhanced by ascorbic acid and preventable by catalase. Redox cycles, feasible only with Cas IIgly, may be an important difference in their mode of action.
Casiopeína IIgly（Cas IIgly）[Cu（4,7-二甲基-1,10-菲咯啉）（甘氨酸盐）]NO（3）与已知的抗癌药物顺铂（CDDP）一样，可诱导不同的人类肿瘤细胞株发生氧化损伤。
比较 Cas IIgly 和 CDDP 在小鼠黑色素瘤 B16 细胞中诱导的谷胱甘肽（GSH）耗竭及其与抗增殖作用的关系。
根据磺基罗丹明 B 测定法测定细胞生长情况。通过还原 Ellman 试剂（DTNB）测量细胞内 GSH 水平。
B16 细胞 Cas IIgly 的 IC50 为 54.5μM（24.21μg/mL），在 30 分钟孵育期内将 GSH 从每百万细胞 1092 耗竭至 585ng。另一方面，在相同条件下，CDDP 的毒性较低，IC50 等于 197.76μM（59.33μg/mL），并且仅在较长的暴露时间（4 小时）后才将 GSH 耗竭至正常水平的 50%。添加 1.8mM 抗坏血酸（Asc）或 1mM 丁硫氨酸亚砜（BSO）增强了 Cas IIgly 的毒性，而 100U/mL 过氧化氢酶则可预防 Cas IIgly 的毒性。BSO 使 B16 细胞对 CDDP 敏感，但 Asc 或过氧化氢酶均未改变 CDDP 的作用。
两种药物的抗增殖作用与细胞内 GSH 水平相关。与 CDDP 不同，Cas IIgly 诱导的 GSH 耗竭发生较早，抗坏血酸可增强其作用，而过氧化氢酶可预防其作用。只有 Cas IIgly 才能进行的氧化还原循环可能是它们作用方式的重要区别。
