A Multisystemic Approach Revealed Aminated Polystyrene Nanoparticles-Induced Neurotoxicity.

Exposure to plastic nanoparticles has dramatically increased in the last 50 years, and there is evidence that plastic nanoparticles can be absorbed by organisms and cross the blood-brain-barrier (BBB). However, their toxic effects, especially on the nervous system, have not yet been extensively investigated, and most of the knowledge is based on studies using different conditions and systems, thus hard to compare. In this work, physicochemical properties of non-modified polystyrene (PS) and amine-functionalized PS (PS-NH2 ) nanoparticles are initially characterized. Advantage of a multisystemic approach is then taken to compare plastic nanoparticles effects in vitro, through cytotoxic readouts in mammalian cell culture, and in vivo, through behavioral readouts in the nematode Caenorhabditis elegans (C. elegans), a powerful 3R-complying model organism for toxicology studies. In vitro experiments in neuroblastoma cells indicate a specific cytotoxic effect of PS-NH2 particles, including a decreased neuronal differentiation and an increased Amyloid ß (Aß) secretion, a sensitive readout correlating with Alzheimer's disease pathology. In parallel, only in vivo treatments with PS-NH2 particles affect C. elegans development, decrease lifespan, and reveal higher sensitivity of animals expressing human Aß compared to wild-type animals. In summary, the multisystemic approach discloses a neurotoxic effect induced by aminated polystyrene nanoparticles.

Nanoplastic Toxicity: Insights and Challenges from Experimental Model Systems.

Nanoplastic particles (NPs) can be produced or derived from the degradation of several daily used products and can therefore be found in the air, water, and food. Every day, these microscopic particles are confronted by different routes of exposure. Recent investigations have shown the internalization of these particles, differing in size and modification, in vivo in aquatic organisms and terrestrial organisms, as well as in vitro in different human cell lines. During the last years, the number of studies investigating the effects of NPs using widely different model systems and experimental approaches is exponentially growing, thus providing information about NPs, especially about polystyrene particle toxicity on health. To facilitate the grasping of the most relevant information, an overview is provided on the toxic effects of NPs coming from studies in cellular systems and in vivo in model organisms and on aspects which can be of particular relevance for particle toxicity (e.g., particle internalization mechanisms and structural modifications). Major achievements and gaps in the field as well as the point of view on how more systematic studies and exploitation of in vivo model organisms may improve the knowledge on important aspects of NPs are also pointed out.