RESEARCH Open Access Filamentous aggregations e u

is available at the end of the articleIntroduction Multiple system atrophy (MSA) is an adult-onset neuro-degenerative disorder manifested clinically as a combin-ation of parkinsonism, cerebellar ataxia and autonomic dysfunction. MSA is now divided into two clinical subtypes: MSA with predominant parkinsonian features (MSA-P) and MSA with predominant cerebellar dysfunc-tion (MSA-C) [1]. MSA is characterized pathologically by any combination of coexisting olivopontocerebellar atro-phy, striatonigral degeneration and preganglionic autonomic lesions [2]. The histological hallmark of MSA is widespread glial cytoplasmic inclusions (GCIs) in the central nervous system [3–6]. These GCIs can be visual-ized by silver staining such as the Gallyas-Braak method [3], and ultrastructurally they consist of granule-associated filaments 20–30 nm in diameter [3, 4, 7]. The major component of GCIs is α-synuclein [8], which is phosphorylated at Serine 129 [9] and ubiquitinated [10]. Although primary oligodendroglial pathology is the main feature of MSA [11–13], accumulation of phos-phorylated α-synuclein is also consistently found in the neuronal cytoplasm, processes and nuclei [14]. Similar neuronal inclusions are found less frequently in the peripheral sympathetic ganglia [13, 15]