Technique for Intranasal Administration of α-Synuclein Aggregates

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the presence of Lewy bodies, which are aggregates of α-synuclein (α-Syn). Recently, the disease was proposed to develop and progress through the prion-like propagation of α-Syn aggregates from the olfactory bulb (OB) or dorsal nucleus of the vagus nerve. Although the origin of α-Syn aggregates in the OB remains unclear, their propagation from the olfactory mucosa has been recently suggested. We previously showed that intranasal administration of α-Syn aggregates in a mouse model induced α-Syn pathology in the OB of mice. In this study, we present a method of intranasal administration of α-Syn aggregates that induced α-Syn pathology in the OB of mice. Intranasal administration of α-Syn aggregates is a very simple and straightforward method, and we believe it will be a useful tool in the research for elucidating the origin of α-Syn pathology in the OB and the pathway of α-Syn propagation through the olfactory system.