Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, 14040-903 Ribeirão Preto, Brazil.
Mutat Res. 2011 Oct 9;725(1-2):50-6. doi: 10.1016/j.mrgentox.2011.06.009. Epub 2011 Jul 6.
We investigated the effects of the dietary pigment chlorophyll b (CLb) on cisplatin (cDDP)-induced oxidative stress and DNA damage, using the comet assay in mouse peripheral blood cells and the micronucleus (MN) test in bone marrow and peripheral blood cells. We also tested for thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) in liver and kidney tissues, as well as catalase (CAT) activity and GSH in total blood. CLb (0.2 and 0.5mg/kg b.w.) was administrated by gavage every day for 13 days. On the 14th day of the experiment, 6 mg/kg cDDP or saline was delivered intraperitoneally. Treatment with cDDP led to a significant decrease in DNA migration and an increase in MN frequency in both cell types, bone marrow and peripheral blood cells. In the kidneys of mice treated with cDDP, TBARS levels were increased, whereas GSH levels were depleted in kidney and liver. In mice that were pre-treated with CLb and then treated with cDDP, TBARS levels maintained normal concentrations and GSH did not differ from cDDP group. The improvement of oxidative stress biomarkers after CLb pre-treatment was associated with a decrease in DNA damage, mainly for the highest dose evaluated. Furthermore, CLb also slightly reduced the frequency of chromosomal breakage and micronucleus formation in mouse bone marrow and peripheral blood cells. These results show that pre-treatment with CLb attenuates cDDP-induced oxidative stress, chromosome instability, and lipid peroxidation.
我们研究了膳食色素叶绿素 b（CLb）对顺铂（cDDP）诱导的氧化应激和 DNA 损伤的影响，使用彗星试验检测小鼠外周血白细胞中的 DNA 损伤，微核试验检测骨髓和外周血白细胞中的染色体断裂。我们还检测了肝和肾组织中的硫代巴比妥酸反应物（TBARS）和还原型谷胱甘肽（GSH）、血液中的过氧化氢酶（CAT）活性和总 GSH。CLb（0.2 和 0.5mg/kg b.w.）通过灌胃每天给药 13 天。在实验的第 14 天，腹腔内给予 6mg/kg cDDP 或生理盐水。用 cDDP 处理导致 DNA 迁移明显减少，骨髓和外周血白细胞中的微核频率增加。用 cDDP 处理的小鼠肾脏中 TBARS 水平升高，而 GSH 水平在肾脏和肝脏中耗竭。用 CLb 预处理然后用 cDDP 处理的小鼠中，TBARS 水平保持正常浓度，GSH 与 cDDP 组无差异。CLb 预处理后氧化应激生物标志物的改善与 DNA 损伤的减少有关，主要与评估的最高剂量有关。此外，CLb 还略微降低了小鼠骨髓和外周血白细胞中染色体断裂和微核形成的频率。这些结果表明，CLb 预处理可减轻 cDDP 诱导的氧化应激、染色体不稳定性和脂质过氧化。
