Increased Oxidative Stress Exacerbates α-Synuclein Aggregation In Vivo

Area of Science:

• Neuroscience
• Biochemistry
• Pathology

Background:

• Oxidative stress is linked to alpha-synuclein aggregation in Parkinson disease (PD).
• A direct in vivo causal link between oxidative stress and PD pathology remains unconfirmed.
• Mitochondrial Superoxide Dismutase 2 (SOD2) is crucial for managing oxidative stress.

Purpose of the Study:

• To investigate the in vivo interaction between oxidative stress and alpha-synuclein aggregation in a PD mouse model.
• To determine if reduced antioxidant capacity exacerbates PD-related pathology.

Main Methods:

• Generated a transgenic PD mouse model with partial SOD2 deficiency (haplodeficiency).
• Utilized the (Thy-1)-h[A30P]-α-synuclein transgenic line.
• Compared synucleinopathy progression in SOD2-deficient mice versus controls at 16 months.

Main Results:

• SOD2-haplodeficient PD mice showed significantly advanced synucleinopathy.
• Higher PK-PET blot scores (p < 0.01) were observed in SOD2-deficient mice.
• Increased truncated alpha-synuclein in brain insoluble fractions (p < 0.05) was noted.

Conclusions:

• Compromising free radical scavenging capacity worsens alpha-synuclein aggregation.
• Elevated oxidative stress can modulate Parkinson disease progression.
• This study provides in vivo evidence for oxidative stress's role in PD pathogenesis.