Longitudinal changes in CSF alpha-synuclein species reflect Parkinson's disease progression

Area of Science:

• Neuroscience
• Biomarker Discovery
• Neurodegenerative Diseases

Background:

• Parkinson's disease (PD) diagnosis relies on clinical criteria, leading to potential misdiagnosis.
• Identifying reliable biomarkers is crucial for tracking PD progression and developing effective therapies.

Purpose of the Study:

• Investigate longitudinal changes in cerebrospinal fluid (CSF) alpha-synuclein species in early PD patients.
• Explore the potential of these CSF alpha-synuclein species as biomarkers for PD progression.

Main Methods:

• Utilized newly developed enzyme-linked immunosorbent assays to measure oligomeric, phosphorylated (serine 129), and total alpha-synuclein in CSF.
• Analyzed samples from 121 participants in the longitudinal Deprenyl and Tocopherol Antioxidative Therapy for Parkinsonism study.
• Measured CSF Alzheimer's disease biomarkers (total-tau, phosphorylated-tau, Aβ40, Aβ42) for comparative analysis.

Main Results:

• Total and oligomeric alpha-synuclein levels significantly increased over a 2-year follow-up.
• Phosphorylated alpha-synuclein at serine 129 levels showed a longitudinal decrease.
• Changes in the oligomeric/total alpha-synuclein ratio correlated with worsening motor signs, particularly in the postural instability and gait difficulty PD subtype.
• A strong positive correlation (r=0.84, P<.001) was observed between changes in CSF total and oligomeric alpha-synuclein.

Conclusions:

• CSF alpha-synuclein species exhibit dynamic changes throughout the course of Parkinson's disease.
• These findings support the potential role of CSF alpha-synuclein species as progression biomarkers for PD.
• The study highlights the link between CSF alpha-synuclein dynamics and specific PD clinical phenotypes.