Dietary energy intake modifies brainstem autonomic dysfunction caused by mutant α-synuclein

Area of Science:

• Neuroscience
• Cardiovascular Physiology
• Autonomic Nervous System Research

Background:

• Parkinson's disease (PD) is linked to autonomic nervous system (ANS) dysfunction, potentially preceding motor symptoms.
• Brainstem pathology, including alpha-synuclein accumulation, is implicated in early PD, but mechanisms of autonomic neuron dysfunction remain unclear.

Purpose of the Study:

• To establish a mouse model for studying early brainstem autonomic control dysregulation in Parkinson's disease.
• To investigate the role of mutant alpha-synuclein in early autonomic dysfunction and cardiovascular abnormalities in PD.

Main Methods:

• Utilized mice expressing a familial PD-associated mutant alpha-synuclein.
• Assessed autonomic control of heart rate, cardiovascular stress response, and parasympathetic activity.
• Examined alpha-synuclein accumulation in the brainstem.

Main Results:

• Mice showed elevated resting heart rate and impaired cardiovascular stress response, indicating aberrant autonomic control.
• Reduced parasympathetic activity and brainstem alpha-synuclein accumulation were observed.
• High-energy diets exacerbated alpha-synuclein effects, while intermittent energy restriction ameliorated them.

Conclusions:

• Established a mouse model for early brainstem cardiovascular dysregulation in Parkinson's disease.
• Demonstrated that mutant alpha-synuclein causes early ANS abnormalities.
• Suggests energy restriction as a potential therapeutic strategy to mitigate ANS dysfunction in PD, especially in overweight individuals.