@article{WulfBarkovitsSchorketal.2022, author = {Wulf, Maximilian and Barkovits, Katalin and Schork, Karin and Eisenacher, Martin and Riederer, Peter and Gerlach, Manfred and Eggers, Britta and Marcus, Katrin}, title = {The proteome of neuromelanin granules in dementia with Lewy bodies}, series = {Cells}, volume = {11}, journal = {Cells}, number = {22}, issn = {2073-4409}, doi = {10.3390/cells11223538}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297465}, year = {2022}, abstract = {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.}, language = {en} } @article{PlumEggersHellingetal.2020, author = {Plum, Sarah and Eggers, Britta and Helling, Stefan and Stepath, Markus and Theiss, Carsten and Leite, Renata E. P. and Molina, Mariana and Grinberg, Lea T. and Riederer, Peter and Gerlach, Manfred and May, Caroline and Marcus, Katrin}, title = {Proteomic characterization of synaptosomes from human substantia nigra indicates altered mitochondrial translation in Parkinson's disease}, series = {Cells}, volume = {9}, journal = {Cells}, number = {12}, issn = {2073-4409}, doi = {10.3390/cells9122580}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219978}, year = {2020}, abstract = {The pathological hallmark of Parkinson's disease (PD) is the loss of neuromelanin-containing dopaminergic neurons within the substantia nigra pars compacta (SNpc). Additionally, numerous studies indicate an altered synaptic function during disease progression. To gain new insights into the molecular processes underlying the alteration of synaptic function in PD, a proteomic study was performed. Therefore, synaptosomes were isolated by density gradient centrifugation from SNpc tissue of individuals at advanced PD stages (N = 5) as well as control subjects free of pathology (N = 5) followed by mass spectrometry-based analysis. In total, 362 proteins were identified and assigned to the synaptosomal core proteome. This core proteome comprised all proteins expressed within the synapses without regard to data analysis software, gender, age, or disease. The differential analysis between control subjects and PD cases revealed that CD9 antigen was overrepresented and fourteen proteins, among them Thymidine kinase 2 (TK2), mitochondrial, 39S ribosomal protein L37, neurolysin, and Methionine-tRNA ligase (MARS2) were underrepresented in PD suggesting an alteration in mitochondrial translation within synaptosomes.}, language = {en} } @article{PlumSteinbachAttemsetal.2016, author = {Plum, Sarah and Steinbach, Simone and Attems, Johannes and Keers, Sharon and Riederer, Peter and Gerlach, Manfred and May, Caroline and Marcus, Katrin}, title = {Proteomic characterization of neuromelanin granules isolated from human substantia nigra by laser-microdissection}, series = {Scientific Reports}, volume = {6}, journal = {Scientific Reports}, number = {37139}, doi = {10.1038/srep37139}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167507}, year = {2016}, abstract = {Neuromelanin is a complex polymer pigment found primarily in the dopaminergic neurons of human substantia nigra. Neuromelanin pigment is stored in granules including a protein matrix and lipid droplets. Neuromelanin granules are yet only partially characterised regarding their structure and function. To clarify the exact function of neuromelanin granules in humans, their enrichment and in-depth characterization from human substantia nigra is necessary. Previously published global proteome studies of neuromelanin granules in human substantia nigra required high tissue amounts. Due to the limited availability of human brain tissue we established a new method based on laser microdissection combined with mass spectrometry for the isolation and analysis of neuromelanin granules. With this method it is possible for the first time to isolate a sufficient amount of neuromelanin granules for global proteomics analysis from ten 10 μm tissue sections. In total 1,000 proteins were identified associated with neuromelanin granules. More than 68\% of those proteins were also identified in previously performed studies. Our results confirm and further extend previously described findings, supporting the connection of neuromelanin granules to iron homeostasis and lysosomes or endosomes. Hence, this method is suitable for the donor specific enrichment and proteomic analysis of neuromelanin granules.}, language = {en} } @article{GerlachMaetzlerBroichetal.2012, author = {Gerlach, Manfred and Maetzler, Walter and Broich, Karl and Hampel, Harald and Rems, Lucas and Reum, Torsten and Riederer, Peter and St{\"a}ffler, Albrecht and Streffer, Johannes and Berg, Daniela}, title = {Biomarker candidates of neurodegeneration in Parkinson's disease for the evaluation of disease-modifying therapeutics}, series = {Journal of Neural Transmission}, volume = {119}, journal = {Journal of Neural Transmission}, number = {1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125375}, pages = {39-52}, year = {2012}, abstract = {Reliable biomarkers that can be used for early diagnosis and tracking disease progression are the cornerstone of the development of disease-modifying treatments for Parkinson's disease (PD). The German Society of Experimental and Clinical Neurotherapeutics (GESENT) has convened a Working Group to review the current status of proposed biomarkers of neurodegeneration according to the following criteria and to develop a consensus statement on biomarker candidates for evaluation of disease-modifying therapeutics in PD. The criteria proposed are that the biomarker should be linked to fundamental features of PD neuropathology and mechanisms underlying neurodegeneration in PD, should be correlated to disease progression assessed by clinical rating scales, should monitor the actual disease status, should be pre-clinically validated, and confirmed by at least two independent studies conducted by qualified investigators with the results published in peer-reviewed journals. To date, available data have not yet revealed one reliable biomarker to detect early neurodegeneration in PD and to detect and monitor effects of drug candidates on the disease process, but some promising biomarker candidates, such as antibodies against neuromelanin, pathological forms of α-synuclein, DJ-1, and patterns of gene expression, metabolomic and protein profiling exist. Almost all of the biomarker candidates were not investigated in relation to effects of treatment, validated in experimental models of PD and confirmed in independent studies.}, language = {en} } @article{GerlachMaetzlerBroichetal.2011, author = {Gerlach, Manfred and Maetzler, Walter and Broich, Karl and Hampel, Harald and Rems, Lucas and Reum, Torsten and Riederer, Peter and St{\"o}ffler, Albrecht and Streffer, Johannes and Berg, Daniela}, title = {Biomarker candidates of neurodegeneration in Parkinson's disease for the evaluation of disease-modifying therapeutics}, series = {Journal of Neural Transmission}, volume = {119}, journal = {Journal of Neural Transmission}, number = {1}, doi = {10.1007/s00702-011-0682-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133856}, pages = {39-52}, year = {2011}, abstract = {Reliable biomarkers that can be used for early diagnosis and tracking disease progression are the cornerstone of the development of disease-modifying treatments for Parkinson's disease (PD). The German Society of Experimental and Clinical Neurotherapeutics (GESENT) has convened a Working Group to review the current status of proposed biomarkers of neurodegeneration according to the following criteria and to develop a consensus statement on biomarker candidates for evaluation of disease-modifying therapeutics in PD. The criteria proposed are that the biomarker should be linked to fundamental features of PD neuropathology and mechanisms underlying neurodegeneration in PD, should be correlated to disease progression assessed by clinical rating scales, should monitor the actual disease status, should be pre-clinically validated, and confirmed by at least two independent studies conducted by qualified investigators with the results published in peer-reviewed journals. To date, available data have not yet revealed one reliable biomarker to detect early neurodegeneration in PD and to detect and monitor effects of drug candidates on the disease process, but some promising biomarker candidates, such as antibodies against neuromelanin, pathological forms of α-synuclein, DJ-1, and patterns of gene expression, metabolomic and protein profiling exist. Almost all of the biomarker candidates were not investigated in relation to effects of treatment, validated in experimental models of PD and confirmed in independent studies.}, language = {en} }