Copper Oxide Nanoparticles Cause a Dose-Dependent Toxicity via Inducing Reactive Oxygen Species in Drosophila

Abstract

Copper oxide nanoparticles (CuONPs) have attracted considerable attention, because of their biocide potential and capability for optical imaging, however CuONPs were shown to be highly toxic in various experimental model systems. In this study, mechanism underlying CuONP-induced toxicity was investigated using Drosophila as an in vivo model. Upon oral route of administration, CuONPs accumulated in the body, and caused a dose-dependent decrease in egg-to-adult survivorship and a delay in development. In particular, transmission electron microscopy analysis revealed CuONPs were detected inside the intestinal epithelial cells and lumen. A drastic increase in apoptosis and reactive oxygen species was also observed in the gut exposed to CuONPs. Importantly, we found that inhibition of the transcription factor Nrf2 further enhances the toxicity caused by CuONPs. These observations suggest that CuONPs disrupt the gut homeostasis and that oxidative stress serves as one of the primary causes of CuONP-induced toxicity in Drosophila.

Fabrication of monodispersed copper oxide nanoparticles with potential application as antimicrobial agents

“…A significant increase in ROS and associated decrease in cell viability in a dose dependent manner, indicates that ROS could have contributed to cell membrane leakage and inflammation, resulting in cell-cycle arrest and subsequent cell death through generation of oxidative stress 65 . Our results are in accordance with previous studies that treatment of cells with Cu 2 O NPs can cause cytotoxicity and DNA damage to biomolecules such as DNA, proteins and lipids through generation of significant amount of ROS induced oxidative stress 52,53 .…”

The Current Understanding of Autophagy in Nanomaterial Toxicity and Its Implementation in Safety Assessment-Related Alternative Testing Strategies

“…Furthermore, AgNPs shortened the life span and reduced the stress resistance capacity of the adult flies [45]. Interestingly, other nanomaterials, such as copper oxide nanoparticles (CuONPs), also induced toxicity in Drosophila via ROS; whether CuONPs and other nanomaterials also induce autophagy in Drosophila remains to be explored [102]. As basal autophagy provides a protection mechanism and thus is generally considered a promoter of longevity [103], it is a possibility that AgNPs-induced autophagy activation plays an important role in aging and longevity.…”

The Influence of Available Cu and Au Nanoparticles (NPs) on the Survival of Water Fleas (Daphnia pulex)

“…Higher number of multiplied daphnia can be observed at low concentrations than in the control for both 24-h and 48-h incubation. This may be related to the fungicidal and antibacterial properties of the nanoparticles [10,12], which provide better conditions for mature daphnia to reproduce. Also under the influence of a stress factor such as the addition of a small amount of Cu NPs, survival is more important for daphnia than keeping the offspring alive, which may explain why there are more newborn daphnias in these concentrations compared to the control.…”

“…The annual worldwide production of Cu-NPs and CuO-NPs is estimated at 200 tons [9] of the products in different concentrations. Among the nanocolloids available on the market, copper has the strongest fungicidal [10,11] and antibacterial [12,13,14,15] effects. Non-ionic colloids of nano-copper can be used to improve the appearance of skin and hair, and against fungal infections in foot care.…”