Genotoxicity of nicotine in cell culture of Caenorhabditis elegans evaluated by the comet assay.
To assess the genotoxicity of nicotine, its DNA-damaging effect on Caenorhabditis elegans cells was tested with the alkaline single-cell microgel electrophoresis (comet) assay. The degree of DNA migration (a measure of possible DNA single-strand breaks, alkali-labile sites, and incomplete excision repair sites) was expressed as the head DNA%, tail length, and Olive tail moment. Large differences were found between experimental variants: 0, 1, 10, and 100 microM (-)-nicotine. At concentrations of 1 and 10 microM, no damages were detected by the comet assay, and the Olive tail moment and tail length were significantly lower than in the control (P < 0.001). The highest head DNA% and the lowest tail length and Olive tail moment were observed in the presence of 1 microM of nicotine. At 100 microM of nicotine, a significant increase (P < 0.001) was observed in Olive tail moment and tail length (up to 2.7- and 3-fold, respectively, compared to the control). The results are consistent with the lowest head DNA% among the three tested variants. This study demonstrated that nicotine treatment had dose-dependent effects on the level of DNA damage. Generally, a high dose of nicotine (100 microM) is genotoxic, while a reasonably low concentration has a protective effect. The possible participation of reactive oxygen species in the DNA-damaging potential of nicotine in C. elegans is discussed.
Sobkowiak
Robert
R
Department of Cell Biology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland. robsob@amu.edu.pl
Lesicki
Andrzej
A
D000818:Animals; D017173:Caenorhabditis elegans / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D020552:Comet Assay; D004249:DNA Damage; D018509:DNA, Helminth / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008136:Longevity / Q000187:drug effects; D009153:Mutagens / Q000633:toxicity*; D009538:Nicotine / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism
D018509:DNA, Helminth; D009153:Mutagens; D017382:Reactive Oxygen Species; D009538:Nicotine