New Insights into the Toxic Effects of Different Sizes of Nanosilica Particles in Food on the Mouse Bladder: Involving Epithelial–Mesenchymal Transition

Animals are widely exposed to nanosilica as a food additive. However, the negative effects of such nanosilica particles on animals' bladders are unclear. In the present study, we investigated the impact of MPs-SiO₂ on mouse bladder and the underlying mechanisms. Mouse and MBEC cell models exposed to MPs-SiO₂ with different particle sizes were established. At the same time, aminoguanidine hydrochloride (RNS inhibitor) and NF-κB activator were used to further explore its mechanism in vitro. We found that MPs-SiO₂ of three sizes could induce RNS-induced pyroptosis causing EMT both in vitro and in vivo. After inhibiting RNS, the expression of related proteins in downstream pathways was decreased, and fibrosis was alleviated. The above situation was reversed by the addition of NF-κB activator. Furthermore, our data suggest that 300 nm MPs-SiO₂ particles have a greater impact on the bladder than 50 nm particles. This study revealed the potential health risks of MPs-SiO₂ and provided new insights into the toxicology of MPs-SiO₂.