Genotoxicity of intraperitoneal injection of lipoamphiphile CdSe/ZnS quantum dots in rats

• We performed an in vivo rat study of lipoamphiphile-coated CdSe/ZnS Quantum Dots.
• QDs were injected in the peritoneal cavity 24 h before to sample different organs.
• QDs genotoxic effects were present in brain, liver and testicles but not in kidney and lung.
• No oxidative stress, cytokine, Hsp70, and caspase-3 responses were observed.
• In vivo, QDs exerted genotoxic effects in the absence of associated oxidative stress.

The main objective of the present in vivo rat study was to determine the genotoxicity of lipoamphiphile-coated CdSe/ZnS Quantum Dots (QDs), in several organs (brain, liver, kidneys, lungs and testicles). The second objective was to establish the correlations between the QDs genotoxic activity and the oxidative stress, the production of a proinflammatory cytokine (TNF-α), a stress-induced chaperone protein, the phosphorylated heat shock protein 70 (pHsp70), and an increase in the caspase-3 apoptosis factor. Four QDs doses were injected into the peritoneal cavity (5, 5 × 10−1, 5 × 10−2 and 5 × 10−3 μg/kg). DNA lesions in the different organs were measured by the comet assay, and chromosome abnormalities were evaluated by the micronucleus assay on blood reticulocytes (MNRET). Twenty-four hours after the QDs injection, genotoxic effects were observed in the brain and liver and, only for the highest QDs concentration, in testicles. No genotoxic effect was seen in the kidney and lung. The MNRET test revealed a dose–response induction of micronuclei. In parallel, we did neither reveal oxidative stress nor significant variations of TNF-α, pHsp70, and caspase-3. In conclusion, the QDs exerted significant genotoxic effects in the brain and liver, even in the absence of any associated oxidative stress and inflammatory processes.