Silica Nanoparticles Promote α-Synuclein Aggregation and Parkinson's Disease Pathology

Silica nanoparticles (SiO₂ NPs) are increasingly investigated for their potential in drug delivery systems. However, the neurotoxicity of SiO₂ NPs remains to be fully clarified. Previously SiO₂ NPs have been reported to be detected in the central nervous system, especially in the dopaminergic neurons which are deeply involved in Parkinson's disease (PD). In this article, we characterized the effects of SiO₂ NPs on inducing PD-like pathology both in vitro and in vivo. Results showed that SiO₂ NPs promote more severe hyperphosphorylation and aggregation of α-synuclein, mitochondria impairment, oxidative stress, autophagy dysfunction, and neuronal apoptosis in the α-Syn A53T transgenic mice intranasally administrated with SiO₂ NPs compared with the control group. Our findings provide new evidence supporting that SiO₂ NPs exposure might have a strong capability of promoting the initiation and development of PD.