α-Synuclein Pathology in Parkinson's Disease Models

α-Synuclein is a presynaptic protein whose misfolding and aggregation underpin the defining neuropathological hallmark of Parkinson’s disease: the Lewy body. Experimental models that recapitulate α-synuclein pathology range from recombinant adeno-associated viral vector (AAV) overexpression in rodents and non-human primates to stereotaxic injection of pre-formed fibrils (PFFs) and transgenic mouse lines bearing SNCA mutations. These systems have been instrumental in delineating the mechanisms of α-synuclein seeding, cell-to-cell propagation and neurotoxicity. Rodent models reveal progressive dopaminergic terminal loss and motor deficits, while primate studies demonstrate long-distance spread of pathology along neural circuits. Complementary in vitro and in vivo assays have clarified the role of post-translational modifications such as serine-129 phosphorylation in driving aggregate maturation and synaptic dysfunction. Together, these models provide a translational platform for testing aggregation-inhibiting therapeutics, developing imaging biomarkers and exploring environmental or genetic modifiers of disease progression.

Research from Nature Portfolio

Automated behavioural analysis using machine-learning algorithms has enhanced the sensitivity of motor assessments in α-synuclein overexpression mouse models. By applying markerless pose estimation and automated classification, investigators detected subtle impairments in balance beam performance prior to overt dopaminergic loss, facilitating earlier phenotype scoring and reducing observer bias. In a complementary study, viral-vector-mediated overexpression of human α-synuclein in rats was paired with in vivo PET imaging of vesicular monoamine transporter 2 to reveal early synaptic dysfunction. Despite preserved nigral cell bodies, progressive terminal pathology and Ser129-phosphorylated aggregates were observed in striatal axons, linking axonopathy to motor impairment in the absence of cell death.

α-Synuclein Pathology in Parkinson's Disease Models publication trend

The graph below shows the total number of articles in α-synuclein pathology in parkinson's disease models across all publications each year (not limited to Nature Index journals).

Technical terms

α-Synuclein (α-syn): A 140-amino-acid neuronal protein that misfolds into toxic oligomers and fibrils in synucleinopathies.

Lewy body: Intracellular inclusion rich in aggregated α-synuclein, hallmark of Parkinson’s disease and related disorders.

Pre-formed fibrils (PFFs): In vitro assembled α-synuclein aggregates used to seed pathology in animal models.

Adeno-associated viral vector (AAV): A non-pathogenic viral delivery system for targeted gene expression in neural tissues.

Single-chain fragment variable (scFv): Engineered antibody fragment that recognises specific conformations of target proteins.

Markerless pose estimation: Machine-learning technique to track animal movements without physical markers, enabling automated behaviour analysis.

Vesicular monoamine transporter 2 (VMAT2): Presynaptic protein responsible for loading monoamines into synaptic vesicles, measurable by PET imaging.

References

1. Cortical Lewy body injections induce long-distance pathogenic alterations in the non-human primate brain. npj Parkinson's Disease (2023).
2. Aggregation-Inhibiting scFv-Based Therapies Protect Mice against AAV1/2-Induced A53T-α-Synuclein Overexpression. Biomolecules (2023).
3. Viral overexpression of human alpha-synuclein in mouse substantia nigra dopamine neurons results in hyperdopaminergia but no neurodegeneration. Experimental Neurology (2024).
4. Automated procedure to detect subtle motor alterations in the balance beam test in a mouse model of early Parkinson’s disease. Scientific Reports (2024).