TY - JOUR A1 - Sian-Hulsmann, Jeswinder A1 - Riederer, Peter T1 - The nigral coup in Parkinson's Disease by α-synuclein and its associated rebels JF - Cells N2 - The risk of Parkinson's disease increases with age. However, the etiology of the illness remains obscure. It appears highly likely that the neurodegenerative processes involve an array of elements that influence each other. In addition, genetic, endogenous, or exogenous toxins need to be considered as viable partners to the cellular degeneration. There is compelling evidence that indicate the key involvement of modified α-synuclein (Lewy bodies) at the very core of the pathogenesis of the disease. The accumulation of misfolded α-synuclein may be a consequence of some genetic defect or/and a failure of the protein clearance system. Importantly, α-synuclein pathology appears to be a common denominator for many cellular deleterious events such as oxidative stress, mitochondrial dysfunction, dopamine synaptic dysregulation, iron dyshomeostasis, and neuroinflammation. These factors probably employ a common apoptotic/or autophagic route in the final stages to execute cell death. The misfolded α-synuclein inclusions skillfully trigger or navigate these processes and thus amplify the dopamine neuron fatalities. Although the process of neuroinflammation may represent a secondary event, nevertheless, it executes a fundamental role in neurodegeneration. Some viral infections produce parkinsonism and exhibit similar characteristic neuropathological changes such as a modest brain dopamine deficit and α-synuclein pathology. Thus, viral infections may heighten the risk of developing PD. Alternatively, α-synuclein pathology may induce a dysfunctional immune system. Thus, sporadic Parkinson's disease is caused by multifactorial trigger factors and metabolic disturbances, which need to be considered for the development of potential drugs in the disorder. KW - Parkinson's disease KW - substantia nigra KW - alpha-synuclein KW - genetics KW - iron KW - neuroinflammation KW - viruses KW - immunology KW - aging and cell death Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234073 SN - 2073-4409 VL - 10 IS - 3 ER - TY - THES A1 - Kuzkina, Anastasia T1 - Dermal α-synuclein oligomers and aggregates in Parkinson’s disease T1 - Nachweis von Alpha-Synuclein-Oligomeren und -Aggregaten in Hautbiopsien von Parkinson-Patienten N2 - Lewy bodies and Lewy neurites are neuropathological hallmarks of Parkinson’s disease (PD). These depositions in the brain mostly consist of aggregated α-synuclein (α-syn) phosphorylated at Ser129. A number of studies reported detection of phosphorylated α-syn (p-α-syn) in the dermal nerve fibers in Parkinson’s disease. The objective of this study was to investigate whether pathological α-syn accumulations detected in the skin represent aggregated protein. A number of methods aimed at detecting α-syn oligomers and aggregates were first tested and optimized on the brain samples in PD and normal control. These methods included proximity ligation assay (PLA), PET-blot, immunohistochemical (IHC) stains with α-syn aggregate (5G4) or oligomer specific (ASyO5) antibodies and a stain against native α-syn (syn211) after proteinase K (PK) digestion. Subsequently, the most specific methods (stains with 5G4, ASyO5 and syn211 after PK digestion) were studied in two separate patient and control cohorts. Anti-p-α-syn stain was performed in parallel. Single sections from at least 2 biopsy sites from 44 patients and 22 controls (cohort 1) as well as serial sections of 4 biopsy sites from 27 patients and 5 controls (cohort 2) were systematically studied for presence of aggregated and oligomeric α-syn. In total, 5G4 positive deposits were found in 24% (cohort 1) and 37% (cohort 2), ASyO5 positive lesions in 17,7% (cohort 1) and 33% (cohort 2), syn211 positive lesions after PK digestion in 38,7% (cohort 1) and 48% (cohort 2) of cases. There was a major overlap among positivity for a particular staining on the patient level and in most cases, the same nerve fiber was found to be positive for all 4 markers in neighboring sections. Among the skin biopsies which contained p-α-syn accumulation, 59% were also PK resistant, 41% were 5G4 positive and 45% were ASyO5 positive. The samples belonging to normal controls did not show any positive signal in either of the newly established stainings or in the anti-p-α-syn staining. Using 3 distinct IHC methods, α-syn oligomers and aggregates were detectable in the majority of p-α-syn positive skin biopsies. This finding supports the hypothesis that α-syn aggregation occurs in the peripheral (i.e. dermal) nerves and can be specifically detected using skin biopsy. N2 - Die neuropathologischen Kennzeichen des Morbus Parkinson sind Lewy-Körperchen und Lewy-Neuriten. Diese Ablagerungen im Gehirn bestehen hauptsächlich aus aggregiertem α-Synuclein (α-Syn), das am Ser129 phosphoryliert ist. Mehrere Studien konnten zeigen, dass phosphoryliertes α-Syn (p-α-Syn) auch in Nervenfasern der Haut von Parkinsonpatienten nachweisbar ist. Das Ziel dieser Arbeit war, zu untersuchen, ob es sich bei den pathologischen Ablagerungen von p-α-Syn in der Haut wie im Gehirn um Aggregate handelt. Mehrere Methoden, die dem Nachweis von α-Syn-Oligomere und Aggregate dienen, wurden zuerst an Gehirnen von einem Parkinsonpatienten und Normalkontrolle getestet und optimiert, darunter: Proximity Ligation Assay (PLA), PET-Blot, immunhistochemische Färbungen mit α-Syn-Aggregat- (5G4) oder Oligomer-spezifischen Antikörper (ASyO5) und eine Färbung mit einem Antikörper gegen natives α-Syn (syn211) nach Verdau mit Proteinase K (PK). Danach wurden die spezifischsten Methoden (Färbung mit 5G4, ASyO5 und syn211 nach PK-Verdau) an den Hautstanzbiopsien von zwei Patienten- und Normalkontrollkohorten untersucht. Parallel wurde in den Biopsien das p-α-Syn angefärbt. Einzelschnitte von je mind. 2 Biopsiestellen von 44 Patienten und 22 Kontrollen (Kohorte 1) sowie Serienschnitte von je 4 Biopsiestellen von 27 Patienten und 5 Kontrollen (Kohorte 2) wurden systematisch nach Vorliegen von aggregierten und oligomerischen α-Syn untersucht. Zusammenfassend, wurden 5G4-positive Ablagerungen in 24% (Kohorte 1) und 37% (2. Kohorte), ASyO5-positive Läsionen in 17,7% (Kohorte 1) und 33% (Kohorte 2), syn211-positive Läsionen nach PK-Verdau in 38,7% (Kohorte 1) und 48% (Kohorte 2) der Fälle gefunden. Das p-α-Syn wurde entsprechend in 43,6% und 48% der Fälle detektiert. Es zeigte sich die Tendenz, dass Patienten, bei denen p-α-Syn nachweisbar war, auch für mehrere der neuen Marker positiv waren; auch häufig waren für alle 4 Marker positive Nervenfasern in naheliegenden Schnitte zu sehen, was für eine Kolokalisation spricht. Unter den Hautbiopsien, in den p-α-Syn-Ablagerungen zu sehen waren, hatten 59% gleichzeitig PK-resistente, 41% 5G4- und 45% ASyO5-positive Ablagerungen. Bei Kontrollen waren Ablagerungen weder mit den neu eingeführten Methoden noch mit anti-p-α-Syn-Färbung detektierbar. Mit Hilfe von drei unterschiedlichen immunhistochemischen Methoden waren Oligomere und Aggregate vom α-Syn im Großteil der p-α-Syn-positiven Hautbiopsien nachweisbar. Dieser Befund unterstützt die Hypothese, dass die Ablagerung von α-Syn-Aggregaten auch in peripheren (v.a. dermalen) Nerven vorkommt und spezifisch nachgewiesen werden kann. KW - Parkinson-Krankheit KW - Biomarker KW - Haut KW - Biopsie KW - parkinson's disease KW - skin biopsy KW - alpha-synuclein KW - biomarker Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-204369 ER - TY - JOUR A1 - Molochnikov, Leonid A1 - Rabey, Jose M. A1 - Dobronevsky, Evgenya A1 - Bonuccelli, Ubaldo A1 - Ceravolo, Roberto A1 - Frosini, Daniela A1 - Grünblatt, Edna A1 - Riederer, Peter A1 - Jacob, Christian A1 - Aharon-Peretz, Judith A1 - Bashenko, Yulia A1 - Youdim, Moussa B. H. A1 - Mandel, Silvia A. T1 - A molecular signature in blood identifies early Parkinson's disease JF - Molecular Neurodegeneration N2 - Background: The search for biomarkers in Parkinson's disease (PD) is crucial to identify the disease early and monitor the effectiveness of neuroprotective therapies. We aim to assess whether a gene signature could be detected in blood from early/mild PD patients that could support the diagnosis of early PD, focusing on genes found particularly altered in the substantia nigra of sporadic PD. Results: The transcriptional expression of seven selected genes was examined in blood samples from 62 early stage PD patients and 64 healthy age-matched controls. Stepwise multivariate logistic regression analysis identified five genes as optimal predictors of PD: p19 S-phase kinase-associated protein 1A (odds ratio [OR] 0.73; 95% confidence interval [CI] 0.60-0.90), huntingtin interacting protein-2 (OR 1.32; CI 1.08-1.61), aldehyde dehydrogenase family 1 subfamily A1 (OR 0.86; 95% CI 0.75-0.99), 19 S proteasomal protein PSMC4 (OR 0.73; 95% CI 0.60-0.89) and heat shock 70-kDa protein 8 (OR 1.39; 95% CI 1.14-1.70). At a 0.5 cut-off the gene panel yielded a sensitivity and specificity in detecting PD of 90.3 and 89.1 respectively and the area under the receiving operating curve (ROC AUC) was 0.96. The performance of the five-gene classifier on the de novo PD individuals alone composing the early PD cohort (n = 38), resulted in a similar ROC with an AUC of 0.95, indicating the stability of the model and also, that patient medication had no significant effect on the predictive probability (PP) of the classifier for PD risk. The predictive ability of the model was validated in an independent cohort of 30 patients at advanced stage of PD, classifying correctly all cases as PD (100% sensitivity). Notably, the nominal average value of the PP for PD (0.95 (SD = 0.09)) in this cohort was higher than that of the early PD group (0.83 (SD = 0.22)), suggesting a potential for the model to assess disease severity. Lastly, the gene panel fully discriminated between PD and Alzheimer's disease (n = 29). Conclusions: The findings provide evidence on the ability of a five-gene panel to diagnose early/mild PD, with a possible diagnostic value for detection of asymptomatic PD before overt expression of the disorder. KW - cerebrospina KW - magnetic-resonance-spectroscopy KW - protein KW - biomarkers KW - E3 ubiquitin ligase KW - SCF KW - SKP1 KW - heat shock protein Hsc-70 KW - early diagnosis KW - fluid KW - alpha-synuclein KW - dehydrogenases KW - Alzheimer's disease KW - sporadic Parkinson's disease KW - blood biomarker KW - CSF KW - multiple system atrophy KW - clinical diagnosis KW - substantia nigra KW - gene expression Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134508 VL - 7 IS - 26 ER -