Specific neuronal populations display high vulnerability to pathological processes in Parkinson’s disease (PD). The dorsal motor nucleus of the vagus nerve (DMnX) is a primary site of pathological α-synuclein deposition and may play a key role in the spreading of α-synuclein lesions within and outside the CNS. Using in vivo models, we show that cholinergic neurons forming this nucleus are particularly susceptible to oxidative challenges and accumulation of ROS. Targeted α-synuclein overexpression within these neurons triggered an oxidative stress that became more pronounced after exposure to the ROS-generating agent paraquat. A more severe oxidative stress resulted in enhanced production of oxidatively modified forms of α-synuclein, increased α-synuclein aggregation into oligomeric species, and marked degeneration of DMnX neurons. Enhanced oxidative stress also affected neuron-to-neuron protein transfer, causing an increased spreading of α-synuclein from the DMnX toward more rostral brain regions. In vitro experiments confirmed a greater propensity of α-synuclein to pass from cell to cell under prooxidant conditions and identified nitrated α-synuclein forms as highly transferable protein species. These findings substantiate the relevance of oxidative injury in PD pathogenetic processes, establish a relationship between oxidative stress and vulnerability to α-synuclein pathology, and define a mechanism, enhanced cell-to-cell α-synuclein transmission, by which oxidative stress could promote PD development and progression.
Ruth E. Musgrove, Michael Helwig, Eun-Jin Bae, Helia Aboutalebi, Seung-Jae Lee, Ayse Ulusoy, Donato A. Di Monte
Usage data is cumulative from June 2019 through December 2019.
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.