Guecheva T, Henriques J A, Erdtmann B
Departamento de Biofísica, Centro de Biotecnologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Prédio 43422, Caixa Postal 15093, CEP 91501-970, RS, Porto Alegre, Brazil.
Mutat Res. 2001 Oct 18;497(1-2):19-27. doi: 10.1016/s1383-5718(01)00244-3.
The alkaline single-cell gel electrophoresis, or comet assay, was used to evaluate the genotoxic potential of copper sulphate in planarians. Concentration-related increase in DNA damage was induced after 2h and 7 days exposure to CuSO4 dissolved in culture water. To study the influence of copper ions on the persistence of mutagen-induced DNA lesions, planarians were treated with methyl methanesulphonate (MMS), and further incubated in the absence (post-incubation) or presence (post-treatment) of CuSO4. After 2h of post-treatment enhanced persistence of DNA effects in relation to the corresponding post-incubation value was detected, which indicate inhibition of DNA repair by CuSO4. At 4h an increase of DNA migration in relation to the 2h value was observed, which is significant for the post-incubation group. After 24h, DNA damage decreased but was still significantly elevated in relation to the control. From our results, we conclude that planarians are suitable organisms for in vivo detection of copper genotoxicity in the comet assay, and can be used to assess both acute and chronic exposure to this chemical in aquatic ecosystems. The inhibition effect of copper ions on repair of MMS-induced DNA damage suggests that copper could modulate the genotoxic effects associated with complex mixture exposure in the environment.
碱性单细胞凝胶电泳法，即彗星试验，被用于评估硫酸铜对涡虫的遗传毒性潜力。将溶解于养殖水中的硫酸铜暴露2小时和7天后，诱导出了与浓度相关的DNA损伤增加。为了研究铜离子对诱变剂诱导的DNA损伤持续性的影响，用甲基磺酸甲酯（MMS）处理涡虫，并在不存在（孵育后）或存在（处理后）硫酸铜的情况下进一步孵育。处理后2小时，检测到与相应孵育后值相比，DNA效应的持续性增强，这表明硫酸铜抑制了DNA修复。在4小时时，与2小时的值相比，观察到DNA迁移增加，这在孵育后组中是显著的。24小时后，DNA损伤减少，但与对照组相比仍显著升高。从我们的结果来看，我们得出结论，涡虫是彗星试验中用于体内检测铜遗传毒性的合适生物，可用于评估水生生态系统中该化学物质的急性和慢性暴露。铜离子对MMS诱导的DNA损伤修复的抑制作用表明，铜可能会调节与环境中复杂混合物暴露相关的遗传毒性效应。
