ABSTRACT
DNA damage response (DDR) pathways in keto-enol genotoxicity have not been characterized, and few studies have reported genotoxic effects in non-target organisms. The present study shows that concentrations of 11.2, 22.4, 37.3 mg/L of Movento® 240SC and 12.3, 24.6, 41.1 mg/L of Envidor® 240SC for 72 h oral exposure induced DSBs by significantly increasing the percentage of γH2AV expression in regions 2b and 3 from the germarium of wild type females of Drosophila melanogaster Oregon R, compared to the control group (0.0 mg/L of insecticides), via confocal immunofluorescence microscopy. The comparison between both insecticides' reveals that only the Envidor® 240SC induces concentration-dependent DNA damage, as well as structural changes in the germarium. We determined that the DDR induced by Movento® 240SC depends on the activation of the ATMtefu, Chk1grp and Chk2lok kinases by significantly increasing the percentage of expression of γH2AV in regions 2b and 3 of the germarium, and that ATRmei-29D and p53dp53 kinases only respond at the highest concentration of 37.3 mg/L of Movento® 240SC. With the Envidor® 240SC insecticide, we determined that the DDR depends on the activation of the ATRmei-29D/Chk1grp and ATMtefu/Chk2lok kinases, and p53dp53 by significantly increasing the percentage of expression of γH2AV in the germarium.
ABSTRACT
Monceren 250 SC is a commercial fungicide with the active ingredient 1-(4-chlorobenzyl)-1-(cyclopentyl)-3-phenylurea, also known as pencycuron. This compound inhibits the growth of fungi as Rhizoctonia solani that invades potato, rice, and cotton or as Pellicularia spp, which contaminates lettuce and tomato crops. In this study, we assessed genotoxicity or DNA damage by the alkaline comet assay in zebrafish blastula-stage embryos exposed to 250 to 1250 µg/mL of the Monceren fungicide or to Bleomycin (0.25 µg/mL) used as a positive control. Additionally, survival and spontaneous movement were monitored in embryos after exposure to different concentrations of fungicide. DNA damage was evaluated using three genotoxicity parameters of the alkaline comet assay: tail length, tail moment, and tail intensity. We found that Monceren 250 SC fungicide induces DNA damage, as shown by significant increases in the three genotoxicity parameters in zebrafish embryos compared with control embryos nonexposed to Monceren. Tail intensity was the more accurate parameter to evaluate genotoxicity levels in zebrafish embryos. At 48 h after exposure to the fungicide, the survival rate of larvae-embryos was reduced to 40-45%. This study shows that the Monceren 250 SC fungicide exerts genotoxic effects in zebrafish during early stages of development.
