Early synaptic dysfunction in Parkinson's disease: Insights from animal models

Area of Science:

• Neuroscience
• Neuropathology
• Molecular Biology

Background:

• Parkinson's disease (PD) motor symptoms are linked to dopaminergic neuron loss in the substantia nigra.
• Traditional PD pathology focused on neuronal cell body degeneration and metabolic product accumulation.
• Emerging evidence suggests early nigrostriatal synapse dysfunction in PD pathogenesis.

Purpose of the Study:

• To review evidence suggesting early synaptic impairment as a key event in Parkinson's disease.
• To integrate findings from pathogenic and genetic animal models of PD.
• To highlight the importance of understanding synaptopathy for developing early biomarkers and novel therapies.

Main Methods:

• Review of neuropathological studies in human brain samples.
• Analysis of in vivo and in vitro experimental models.
• Integration of data from pathogenic and genetic animal models.

Main Results:

• Evidence supports nigrostriatal synapses being affected early in Parkinson's disease.
• Mechanisms of synaptic dysfunction include altered axonal transport, exocytosis/endocytosis, and plasticity.
• Early synaptic impairment is proposed as a central event in PD pathogenesis.

Conclusions:

• Early synaptic dysfunction, or synaptopathy, may be a critical initiating event in Parkinson's disease.
• Understanding these synaptic events is crucial for developing early diagnostic biomarkers.
• Targeting the synaptic apparatus offers a promising strategy for novel Parkinson's disease therapies.