Neurotoxicity of silver nanoparticles stabilized with different coating agents: In vitro response of neuronal precursor cells.

Silver nanoparticles (AgNPs) represent one of the most abundant biocidal nanomaterials contained in more than 30% of nano-enabled consumer products and 75% of nanomedical products. The cumulative exposure of the general population may therefore reach critical and potentially hazardous levels. Due to data gaps on AgNP effects in humans, it is urgent to further evaluate their possible toxicity, particularly in vulnerable systems like the nervous one. As AgNPs may cross the blood brain and placental barriers, this study evaluated the in vitro effect of different AgNPs on neuronal precursor cells. For this purpose, 10 nm-sized AgNPs were stabilized with five different coating agents rendering a neutral, positive and negative surface charge. Murine neural stem cells (mNSCs) were used as cellular model to test AgNP neurotoxicity by evaluating the range of toxicity endpoints including cellular viability, apoptosis induction, oxidative stress response, cellular and mitochondrial membrane damages, DNA damage, inflammation response, and neural stem cell regulation. Our results clearly showed that the neurotoxic potential of AgNPs was not dependent on their surface charge or coating agents used for their surface stabilization. All AgNP types exhibited significant toxicity in neuronal precursor cells at an in vitro dose of 5 mg Ag/L or lower.