Oligomeric Alpha-synuclein in Multiple System Atrophy

Multiple system atrophy (MSA) is a rare neurodegenerative disorder which is characterized by a variable combination of parkinsonism, cerebellar dysfunction, autonomic failure, and additional signs.

No effective treatment is available. Together with PD and Lewy body dementia, MSA belongs to a group of neurodegenerative disorders, the alpha-synucleinopathies, which are characterized by the abnormal accumulation of alpha-synuclein.

The development of biological markers for the diagnosis and prognosis in MSA remains an unmet need. Such biological markers are crucial for future disease-modification and neuroprotection trials. Alpha-synuclein has a high potential for biomarker development since it constitutes the pathological hallmark feature in MSA.

The oligomeric alpha-synuclein seems to be particularly involved in abnormal protein aggregation in alpha-synucleinopathies.

The study will compare alpha-synuclein levels in CSF and plasma between patients suffering from AMS and controls who are patients requiring spinal tap without being affected by a neurodegenerative disorder. The MSA patients and controls will receive CSF and blood sampling at one study visit.

• MSA patients

o Inclusion criteria: Patients suffering from "probable" MSA according to clinical consensus criteria (Gilman et al, 2008), Age >30 Written informed consent Patient covered by the national health system

o exclusion criteria: UMSARS IV score > 4 points Patient under tutelage Patient unable to give consent Patients receiving anticoagulants, showing abnormal coagulation on blood testing or thrombocytopenia are excluded from this study

• Controls (patients requiring spinal tap without suffering from a neurodegenerative disorder) o Inclusion criteria: Patients not suffering from a neurodegenerative disorder and requiring a spinal tap Age >30 Written informed consent Patient covered by the national health system o exclusion criteria: Similar to MSA patients