Multiomic Analysis Reveals Molecular Pathways Associated with Intestinal Aggregation of α-Synuclein

Area of Science:

• Neuroscience
• Gastroenterology
• Cell Biology

Background:

• Parkinson's disease (PD) is linked to alpha-synuclein (α-synuclein) aggregation.
• Enteroendocrine cells in the gut express α-synuclein and connect to the brain via the vagus nerve.
• Gut microbiota metabolites, like nitrite, can induce α-synuclein aggregation in these cells.

Purpose of the Study:

• To investigate the role of dopamine in nitrite-induced α-synuclein aggregation in enteroendocrine cells.
• To explore the cellular and proteomic changes associated with dopamine production and α-synuclein aggregation.
• To identify potential therapeutic strategies targeting gut-based α-synuclein formation.

Main Methods:

• Modulation of dopamine biosynthesis in enteroendocrine cells.
• Proteomic and lipidomic profiling of cells with varying dopamine levels.
• Assessment of cell viability under stress conditions (nitrite, α-synuclein aggregates).
• Testing the effect of benserazide, a dopamine synthesis inhibitor.

Main Results:

• Dopamine production is critical for nitrite-induced α-synuclein aggregation.
• Proteomic profiles differ significantly between dopamine-producing and dopamine-deficient cells.
• Enteroendocrine cells remain viable despite nitrite exposure and α-synuclein aggregates, suggesting a reservoir role.
• Benserazide inhibits α-synuclein aggregate formation in enteroendocrine cells.

Conclusions:

• Dopamine-producing enteroendocrine cells may act as a reservoir for α-synuclein aggregates, facilitating gut-to-brain spread.
• Inhibition of dopamine biosynthesis, using agents like benserazide, shows promise in preventing α-synuclein aggregation in the gut.
• These findings provide a mechanistic basis for developing therapies to prevent PD progression originating from the intestine.