TY  - JOUR
A1  - Wulf, Maximilian
A1  - Barkovits, Katalin
A1  - Schork, Karin
A1  - Eisenacher, Martin
A1  - Riederer, Peter
A1  - Gerlach, Manfred
A1  - Eggers, Britta
A1  - Marcus, Katrin
T1  - The proteome of neuromelanin granules in dementia with Lewy bodies
JF  - Cells
N2  - Neuromelanin granules (NMGs) are organelle-like structures present in the human substantia nigra pars compacta. In addition to neuromelanin, NMGs contain proteins, lipids and metals. As NMG-containing dopaminergic neurons are preferentially lost in Parkinson’s disease and dementia with Lewy bodies (DLB), it is assumed that NMGs may play a role in neurodegenerative processes. Until now, this role is not completely understood and needs further investigation. We therefore set up an exploratory proteomic study to identify differences in the proteomic profile of NMGs from DLB patients (n = 5) compared to healthy controls (CTRL, n = 5). We applied a laser microdissection and mass-spectrometry-based approach, in which we used targeted mass spectrometric experiments for validation. In NMG-surrounding (SN\(_{Surr.}\)) tissue of DLB patients, we found evidence for ongoing oxidative damage and an impairment of protein degradation. As a potentially disease-related mechanism, we found α-synuclein and protein S100A9 to be enriched in NMGs of DLB cases, while the abundance of several ribosomal proteins was significantly decreased. As S100A9 is known to be able to enhance the formation of toxic α-synuclein fibrils, this finding points towards an involvement of NMGs in pathogenesis, however the exact role of NMGs as either neuroprotective or neurotoxic needs to be further investigated. Nevertheless, our study provides evidence for an impairment of protein degradation, ongoing oxidative damage and accumulation of potentially neurotoxic protein aggregates to be central mechanisms of neurodegeneration in DLB.
KW  - neuromelanin granules
KW  - neurodegeneration
KW  - dementia with Lewy bodies
KW  - proteomics
KW  - stress granules
KW  - substantia nigra pars compacta
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-297465
SN  - 2073-4409
VL  - 11
IS  - 22
ER  - 
TY  - JOUR
A1  - Gschmack, Eva
A1  - Monoranu, Camelia-Maria
A1  - Marouf, Hecham
A1  - Meyer, Sarah
A1  - Lessel, Lena
A1  - Idris, Raja
A1  - Berg, Daniela
A1  - Maetzler, Walter
A1  - Steigerwald, Frank
A1  - Volkmann, Jens
A1  - Gerlach, Manfred
A1  - Riederer, Peter
A1  - Koutsilieri, Eleni
A1  - Scheller, Carsten
T1  - Plasma autoantibodies to glial fibrillary acidic protein (GFAP) react with brain areas according to Braak staging of Parkinson’s disease
JF  - Journal of Neural Transmission
N2  - Idiopathic Parkinson’s disease (PD) is characterized by a progredient degeneration of the brain, starting at deep subcortical areas such as the dorsal motor nucleus of the glossopharyngeal and vagal nerves (DM) (stage 1), followed by the coeruleus–subcoeruleus complex; (stage 2), the substantia nigra (SN) (stage 3), the anteromedial temporal mesocortex (MC) (stage 4), high-order sensory association areas and prefrontal fields (HC) (stage 5) and finally first-order sensory association areas, premotor areas, as well as primary sensory and motor field (FC) (stage 6). Autoimmunity might play a role in PD pathogenesis. Here we analyzed whether anti-brain autoantibodies differentially recognize different human brain areas and identified autoantigens that correlate with the above-described dissemination of PD pathology in the brain. Brain tissue was obtained from deceased individuals with no history of neurological or psychiatric disease and no neuropathological abnormalities. Tissue homogenates from different brain regions (DM, SN, MC, HC, FC) were subjected to SDS-PAGE and Western blot. Blots were incubated with plasma samples from 30 PD patients and 30 control subjects and stained with anti-IgG antibodies to detect anti-brain autoantibodies. Signals were quantified. Prominent autoantigens were identified by 2D-gel-coupled mass spectrometry sequencing. Anti-brain autoantibodies are frequent and occur both in healthy controls and individuals with PD. Glial fibrillary acidic protein (GFAP) was identified as a prominent autoantigen recognized in all plasma samples. GFAP immunoreactivity was highest in DM areas and lowest in FC areas with no significant differences in anti-GFAP autoantibody titers between healthy controls and individuals with PD. The anti-GFAP autoimmunoreactivity of different brain areas correlates with the dissemination of histopathological neurodegeneration in PD. We hypothesize that GFAP autoantibodies are physiological but might be involved as a cofactor in PD pathogenesis secondary to a leakage of the blood–brain barrier.
KW  - Parkinson
KW  - GFAP
KW  - autoantibodies
KW  - Braak
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-325161
VL  - 129
IS  - 5-6
ER  -