Multigenerational effects and DNA alterations of QDs-Indolicidin on Daphnia magna

- Toxicity was investigated to look for the risk of QDs-Indolicidin among three generations of Daphnia magna.
- We examine effects of QDs-Indolicidin at individual level evaluating growth, survival and reproduction.
- QDs-Ind induced changes in DNA first in somatic cells (from F0 to F1) then in germ cells (from F1 to F2).
- Changes in gene expression of stress responsive genes (Dhb, Vtg, and CYP4) were found over generations.

The complex QDs-Indolicidin (QDs-Ind) has been previously shown to be a good antimicrobial system with a low acute toxicity on Daphnia magna (D. magna). However, multigenerational effects caused by exposure to QDs-Ind and after subsequent recovery are still unknown. In this study, we performed multigenerational exposure tests and we evaluated individual fitness, population growth, DNA alteration, expression of Dhb (haemoglobin), Vtg (vitellogenin), CYP4 (cytochrome P450s CYP4 family), and CYP314 (cytochrome P450s mitochondrial family 314) genes on three generation of D. magna. Results showed that the total amount of eggs produced per female and total number of brood per female and body lengths were significantly decreased, Dhb, CYP4 were upregulated while Vtg was down-regulated except at reproduction days when it was slightly up-regulated under QDs-Ind exposure. Random Amplification of Polymorphic DNA (RAPD) method has proven to be useful to qualitative assess of DNA damage during generation and to underline modification in somatic or germinal cells. The results of the study suggest that effects of chronic exposure cannot be ignored.

258