@article{GrohBerveMartini2021, author = {Groh, Janos and Berve, Kristina and Martini, Rudolf}, title = {Immune modulation attenuates infantile neuronal ceroid lipofuscinosis in mice before and after disease onset}, series = {Brain Communications}, volume = {3}, journal = {Brain Communications}, number = {2}, doi = {10.1093/braincomms/fcab047}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260167}, year = {2021}, abstract = {Targeting neuroinflammation in models for infantile and juvenile forms of neuronal ceroid lipofuscinosis (NCL, CLN disease) with the clinically established immunomodulators fingolimod and teriflunomide significantly attenuates the neurodegenerative phenotype when applied preventively, i.e. before the development of substantial neural damage and clinical symptoms. Here, we show that in a mouse model for the early onset and rapidly progressing CLN1 form, more complex clinical phenotypes like disturbed motor coordination and impaired visual acuity are also ameliorated by immunomodulation. Moreover, we show that the disease outcome can be attenuated even when fingolimod and teriflunomide treatment starts after disease onset, i.e. when neurodegeneration is ongoing and clinical symptoms are detectable. In detail, treatment with either drug led to a reduction in T-cell numbers and microgliosis in the CNS, although not to the same extent as upon preventive treatment. Pharmacological immunomodulation was accompanied by a reduction of axonal damage, neuron loss and astrogliosis in the retinotectal system and by reduced brain atrophy. Accordingly, the frequency of myoclonic jerks and disturbed motor coordination were attenuated. Overall, disease alleviation was remarkably substantial upon therapeutic treatment with both drugs, although less robust than upon preventive treatment. To test the relevance of putative immune-independent mechanisms of action in this model, we treated CLN1 mice lacking mature T- and B-lymphocytes. Immunodeficient CLN1 mice showed, as previously reported, an improved neurological phenotype in comparison with genuine CLN1 mice which could not be further alleviated by either of the drugs, reflecting a predominantly immune-related therapeutic mechanism of action. The present study supports and strengthens our previous view that repurposing clinically approved immunomodulators may alleviate the course of CLN1 disease in human patients, even though diagnosis usually occurs when symptoms have already emerged.}, language = {en} } @article{BrumbergKuzkinaLapaetal.2021, author = {Brumberg, Joachim and Kuzkina, Anastasia and Lapa, Constantin and Mammadova, Sona and Buck, Andreas and Volkmann, Jens and Sommer, Claudia and Isaias, Ioannis U. and Doppler, Kathrin}, title = {Dermal and cardiac autonomic fiber involvement in Parkinson's disease and multiple system atrophy}, series = {Neurobiology of Disease}, volume = {153}, journal = {Neurobiology of Disease}, doi = {10.1016/j.nbd.2021.105332}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260061}, pages = {105332}, year = {2021}, abstract = {Pathological aggregates of alpha-synuclein in peripheral dermal nerve fibers can be detected in patients with idiopathic Parkinson's disease and multiple system atrophy. This study combines skin biopsy staining for p-alpha-synuclein depositions and radionuclide imaging of the heart with [\(^{123}\)I]-metaiodobenzylguanidine to explore peripheral denervation in both diseases. To this purpose, 42 patients with a clinical diagnosis of Parkinson's disease or multiple system atrophy were enrolled. All patients underwent a standardized clinical workup including neurological evaluation, neurography, and blood samples. Skin biopsies were obtained from the distal and proximal leg, back, and neck for immunofluorescence double labeling with anti-p-alpha-synuclein and anti-PGP9.5. All patients underwent myocardial [\(^{123}\)I]-metaiodobenzylguanidine scintigraphy. Dermal p-alpha-synuclein was observed in 47.6\% of Parkinson's disease patients and was mainly found in autonomic structures. 81.0\% of multiple system atrophy patients had deposits with most of cases in somatosensory fibers. The [\(^{123}\)I]-metaiodobenzylguanidine heart-to-mediastinum ratio was lower in Parkinson's disease than in multiple system atrophy patients (1.94 +/- 0.63 vs. 2.91 +/- 0.96; p < 0.0001). Irrespective of the diagnosis, uptake was lower in patients with than without p-alpha-synuclein in autonomic structures (1.42 +/- 0.51 vs. 2.74 +/- 0.83; p < 0.0001). Rare cases of Parkinson's disease with p-alpha-synuclein in somatosensory fibers and multiple system atrophy patients with deposits in autonomic structures or both fiber types presented with clinically overlapping features. In conclusion, this study suggests that alpha-synuclein contributes to peripheral neurodegeneration and mediates the impairment of cardiac sympathetic neurons in patients with synucleinopathies. Furthermore, it indicates that Parkinson's disease and multiple system atrophy share pathophysiologic mechanisms of peripheral nervous system dysfunction with a clinical overlap.}, language = {en} } @article{EgenolfAltenschildescheKressetal.2021, author = {Egenolf, Nadine and Altenschildesche, Caren Meyer zu and Kreß, Luisa and Eggermann, Katja and Namer, Barbara and Gross, Franziska and Klitsch, Alexander and Malzacher, Tobias and Kampik, Daniel and Malik, Rayaz A. and Kurth, Ingo and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Diagnosing small fiber neuropathy in clinical practice: a deep phenotyping study}, series = {Therapeutic Advances in Neurological Disorders}, volume = {14}, journal = {Therapeutic Advances in Neurological Disorders}, issn = {1756-2864}, doi = {10.1177/17562864211004318}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232019}, year = {2021}, abstract = {Background and aims: Small fiber neuropathy (SFN) is increasingly suspected in patients with pain of uncertain origin, and making the diagnosis remains a challenge lacking a diagnostic gold standard. Methods: In this case-control study, we prospectively recruited 86 patients with a medical history and clinical phenotype suggestive of SFN. Patients underwent neurological examination, quantitative sensory testing (QST), and distal and proximal skin punch biopsy, and were tested for pain-associated gene loci. Fifty-five of these patients additionally underwent pain-related evoked potentials (PREP), corneal confocal microscopy (CCM), and a quantitative sudomotor axon reflex test (QSART). Results: Abnormal distal intraepidermal nerve fiber density (IENFD) (60/86, 70\%) and neurological examination (53/86, 62\%) most frequently reflected small fiber disease. Adding CCM and/or PREP further increased the number of patients with small fiber impairment to 47/55 (85\%). Genetic testing revealed potentially pathogenic gene variants in 14/86 (16\%) index patients. QST, QSART, and proximal IENFD were of lower impact. Conclusion: We propose to diagnose SFN primarily based on the results of neurological examination and distal IENFD, with more detailed phenotyping in specialized centers.}, language = {en} } @article{SchuhmannBieberFrankeetal.2021, author = {Schuhmann, Michael K. and Bieber, Michael and Franke, Maximilian and Kollikowski, Alexander M. and Stegner, David and Heinze, Katrin G. and Nieswandt, Bernhard and Pham, Mirko and Stoll, Guido}, title = {Platelets and lymphocytes drive progressive penumbral tissue loss during middle cerebral artery occlusion in mice}, series = {Journal of Neuroinflammation}, volume = {18}, journal = {Journal of Neuroinflammation}, number = {1}, doi = {10.1186/s12974-021-02095-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259172}, pages = {46}, year = {2021}, abstract = {Background In acute ischemic stroke, cessation of blood flow causes immediate tissue necrosis within the center of the ischemic brain region accompanied by functional failure in the surrounding brain tissue designated the penumbra. The penumbra can be salvaged by timely thrombolysis/thrombectomy, the only available acute stroke treatment to date, but is progressively destroyed by the expansion of infarction. The underlying mechanisms of progressive infarction are not fully understood. Methods To address mechanisms, mice underwent filament occlusion of the middle cerebral artery (MCAO) for up to 4 h. Infarct development was compared between mice treated with antigen-binding fragments (Fab) against the platelet surface molecules GPIb (p0p/B Fab) or rat immunoglobulin G (IgG) Fab as control treatment. Moreover, Rag1\(^{-/-}\) mice lacking T-cells underwent the same procedures. Infarct volumes as well as the local inflammatory response were determined during vessel occlusion. Results We show that blocking of the platelet adhesion receptor, glycoprotein (GP) Ibα in mice, delays cerebral infarct progression already during occlusion and thus before recanalization/reperfusion. This therapeutic effect was accompanied by decreased T-cell infiltration, particularly at the infarct border zone, which during occlusion is supplied by collateral blood flow. Accordingly, mice lacking T-cells were likewise protected from infarct progression under occlusion. Conclusions Progressive brain infarction can be delayed by blocking detrimental lymphocyte/platelet responses already during occlusion paving the way for ultra-early treatment strategies in hyper-acute stroke before recanalization.}, language = {en} } @article{SchuhmannPappStolletal.2021, author = {Schuhmann, Michael K. and Papp, Lena and Stoll, Guido and Blum, Robert and Volkmann, Jens and Fluri, Felix}, title = {Mesencephalic electrical stimulation reduces neuroinflammation after photothrombotic stroke in rats by targeting the cholinergic anti-inflammatory pathway}, series = {International Journal of Molecular Sciences}, volume = {22}, journal = {International Journal of Molecular Sciences}, number = {3}, issn = {1422-0067}, doi = {10.3390/ijms22031254}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259099}, year = {2021}, abstract = {Inflammation is crucial in the pathophysiology of stroke and thus a promising therapeutic target. High-frequency stimulation (HFS) of the mesencephalic locomotor region (MLR) reduces perilesional inflammation after photothrombotic stroke (PTS). However, the underlying mechanism is not completely understood. Since distinct neural and immune cells respond to electrical stimulation by releasing acetylcholine, we hypothesize that HFS might trigger the cholinergic anti-inflammatory pathway via activation of the α7 nicotinic acetylcholine receptor (α7nAchR). To test this hypothesis, rats underwent PTS and implantation of a microelectrode into the MLR. Three hours after intervention, either HFS or sham-stimulation of the MLR was applied for 24 h. IFN-γ, TNF-α, and IL-1α were quantified by cytometric bead array. Choline acetyltransferase (ChAT)\(^+\) CD4\(^+\)-cells and α7nAchR\(^+\)-cells were quantified visually using immunohistochemistry. Phosphorylation of NFĸB, ERK1/2, Akt, and Stat3 was determined by Western blot analyses. IFN-γ, TNF-α, and IL-1α were decreased in the perilesional area of stimulated rats compared to controls. The number of ChAT\(^+\) CD4\(^+\)-cells increased after MLR-HFS, whereas the amount of α7nAchR\(^+\)-cells was similar in both groups. Phospho-ERK1/2 was reduced significantly in stimulated rats. The present study suggests that MLR-HFS may trigger anti-inflammatory processes within the perilesional area by modulating the cholinergic system, probably via activation of the α7nAchR.}, language = {en} } @article{LangeSteigerwaldMalzacheretal.2021, author = {Lange, Florian and Steigerwald, Frank and Malzacher, Tobias and Brandt, Gregor Alexander and Odorfer, Thorsten Michael and Roothans, Jonas and Reich, Martin M. and Fricke, Patrick and Volkmann, Jens and Matthies, Cordula and Capetian, Philipp D.}, title = {Reduced Programming Time and Strong Symptom Control Even in Chronic Course Through Imaging-Based DBS Programming}, series = {Frontiers in Neurology}, volume = {12}, journal = {Frontiers in Neurology}, issn = {1664-2295}, doi = {10.3389/fneur.2021.785529}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-249634}, year = {2021}, abstract = {Objectives: Deep brain stimulation (DBS) programming is based on clinical response testing. Our clinical pilot trial assessed the feasibility of image-guided programing using software depicting the lead location in a patient-specific anatomical model. Methods: Parkinson's disease patients with subthalamic nucleus-DBS were randomly assigned to standard clinical-based programming (CBP) or anatomical-based (imaging-guided) programming (ABP) in an 8-week crossover trial. Programming characteristics and clinical outcomes were evaluated. Results: In 10 patients, both programs led to similar motor symptom control (MDS-UPDRS III) after 4 weeks (medicationOFF/stimulationON; CPB: 18.27 ± 9.23; ABP: 18.37 ± 6.66). Stimulation settings were not significantly different, apart from higher frequency in the baseline program than CBP (p = 0.01) or ABP (p = 0.003). Time spent in a program was not significantly different (CBP: 86.1 ± 29.82\%, ABP: 88.6 ± 29.0\%). Programing time was significantly shorter (p = 0.039) with ABP (19.78 ± 5.86 min) than CBP (45.22 ± 18.32). Conclusion: Image-guided DBS programming in PD patients drastically reduces programming time without compromising symptom control and patient satisfaction in this small feasibility trial.}, language = {en} } @article{PiroEckesKasaragodetal.2021, author = {Piro, Inken and Eckes, Anna-Lena and Kasaragod, Vikram Babu and Sommer, Claudia and Harvey, Robert J. and Schaefer, Natascha and Villmann, Carmen}, title = {Novel Functional Properties of Missense Mutations in the Glycine Receptor β Subunit in Startle Disease}, series = {Frontiers in Molecular Neuroscience}, volume = {14}, journal = {Frontiers in Molecular Neuroscience}, issn = {1662-5099}, doi = {10.3389/fnmol.2021.745275}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246676}, year = {2021}, abstract = {Startle disease is a rare disorder associated with mutations in GLRA1 and GLRB, encoding glycine receptor (GlyR) α1 and β subunits, which enable fast synaptic inhibitory transmission in the spinal cord and brainstem. The GlyR β subunit is important for synaptic localization via interactions with gephyrin and contributes to agonist binding and ion channel conductance. Here, we have studied three GLRB missense mutations, Y252S, S321F, and A455P, identified in startle disease patients. For Y252S in M1 a disrupted stacking interaction with surrounding aromatic residues in M3 and M4 is suggested which is accompanied by an increased EC\(_{50}\) value. By contrast, S321F in M3 might stabilize stacking interactions with aromatic residues in M1 and M4. No significant differences in glycine potency or efficacy were observed for S321F. The A455P variant was not predicted to impact on subunit folding but surprisingly displayed increased maximal currents which were not accompanied by enhanced surface expression, suggesting that A455P is a gain-of-function mutation. All three GlyR β variants are trafficked effectively with the α1 subunit through intracellular compartments and inserted into the cellular membrane. In vivo, the GlyR β subunit is transported together with α1 and the scaffolding protein gephyrin to synaptic sites. The interaction of these proteins was studied using eGFP-gephyrin, forming cytosolic aggregates in non-neuronal cells. eGFP-gephyrin and β subunit co-expression resulted in the recruitment of both wild-type and mutant GlyR β subunits to gephyrin aggregates. However, a significantly lower number of GlyR β aggregates was observed for Y252S, while for mutants S321F and A455P, the area and the perimeter of GlyR β subunit aggregates was increased in comparison to wild-type β. Transfection of hippocampal neurons confirmed differences in GlyR-gephyrin clustering with Y252S and A455P, leading to a significant reduction in GlyR β-positive synapses. Although none of the mutations studied is directly located within the gephyrin-binding motif in the GlyR β M3-M4 loop, we suggest that structural changes within the GlyR β subunit result in differences in GlyR β-gephyrin interactions. Hence, we conclude that loss- or gain-of-function, or alterations in synaptic GlyR clustering may underlie disease pathology in startle disease patients carrying GLRB mutations.}, language = {en} } @article{NguemeniStiehlHiewetal.2021, author = {Nguemeni, Carine and Stiehl, Annika and Hiew, Shawn and Zeller, Daniel}, title = {No Impact of Cerebellar Anodal Transcranial Direct Current Stimulation at Three Different Timings on Motor Learning in a Sequential Finger-Tapping Task}, series = {Frontiers in Human Neuroscience}, volume = {15}, journal = {Frontiers in Human Neuroscience}, issn = {1662-5161}, doi = {10.3389/fnhum.2021.631517}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225477}, year = {2021}, abstract = {Background: Recently, attention has grown toward cerebellar neuromodulation in motor learning using transcranial direct current stimulation (tDCS). An important point of discussion regarding this modulation is the optimal timing of tDCS, as this parameter could significantly influence the outcome. Hence, this study aimed to investigate the effects of the timing of cerebellar anodal tDCS (ca-tDCS) on motor learning using a sequential finger-tapping task (FTT). Methods: One hundred and twenty two healthy young, right-handed subjects (96 females) were randomized into four groups (During\(_{sham}\), Before, During\(_{real}\), After). They performed 2 days of FTT with their non-dominant hand on a custom keyboard. The task consisted of 40 s of typing followed by 20 s rest. Each participant received ca-tDCS (2 mA, sponge electrodes of 25 cm\(^{2}\), 20 min) at the appropriate timing and performed 20 trials on the first day (T1, 20 min). On the following day, only 10 trials of FTT were performed without tDCS (T2, 10 min). Motor skill performance and retention were assessed. Results: All participants showed a time-dependent increase in learning. Motor performance was not different between groups at the end of T1 (p = 0.59). ca-tDCS did not facilitate the retention of the motor skill in the FTT at T2 (p = 0.27). Thus, our findings indicate an absence of the effect of ca-tDCS on motor performance or retention of the FTT independently from the timing of stimulation. Conclusion: The present results suggest that the outcome of ca-tDCS is highly dependent on the task and stimulation parameters. Future studies need to establish a clear basis for the successful and reproducible clinical application of ca-tDCS.}, language = {en} } @article{GesslerLehmannBoeseletal.2021, author = {Gessler, Florian and Lehmann, Felix and B{\"o}sel, Julian and Fuhrer, Hannah and Neugebauer, Hermann and Wartenberg, Katja E. and Wolf, Stefan and Bernstock, Joshua D. and Niesen, Wolf-Dirk and Schuss, Patrick}, title = {Triage and Allocation of Neurocritical Care Resources During the COVID 19 Pandemic - A National Survey}, series = {Frontiers in Neurology}, volume = {11}, journal = {Frontiers in Neurology}, issn = {1664-2295}, doi = {10.3389/fneur.2020.609227}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-221593}, year = {2021}, abstract = {Objective: In light of the ongoing COVID-19 pandemic and the associated hospitalization of an overwhelming number of ventilator-dependent patients, medical and/or ethical patient triage paradigms have become essential. While guidelines on the allocation of scarce resources do exist, such work within the subdisciplines of intensive care (e.g., neurocritical care) remains limited. Methods: A 16-item questionnaire was developed that sought to explore/quantify the expert opinions of German neurointensivists with regard to triage decisions. The anonymous survey was conducted via a web-based platform and in total, 96 members of the Initiative of German Neurointensive Trial Engagement (IGNITE)-study group were contacted via e-mail. The IGNITE consortium consists of an interdisciplinary panel of specialists with expertise in neuro-critical care (i.e., anesthetists, neurologists and neurosurgeons). Results: Fifty members of the IGNITE consortium responded to the questionnaire; in total the respondents were in charge of more than 500 Neuro ICU beds throughout Germany. Common determinants reported which affected triage decisions included known patient wishes (98\%), the state of health before admission (96\%), SOFA-score (85\%) and patient age (69\%). Interestingly, other principles of allocation, such as a treatment of "youngest first" (61\%) and members of the healthcare sector (50\%) were also noted. While these were the most accepted parameters affecting the triage of patients, a "first-come, first-served" principle appeared to be more accepted than a lottery for the allocation of ICU beds which contradicts much of what has been reported within the literature. The respondents also felt that at least one neurointensivist should serve on any interdisciplinary triage team. Conclusions: The data gathered in the context of this survey reveal the estimation/perception of triage algorithms among neurointensive care specialists facing COVID-19. Further, it is apparent that German neurointensivists strongly feel that they should be involved in any triage decisions at an institutional level given the unique resources needed to treat patients within the Neuro ICU.}, language = {en} } @article{KremerPauwelsPozzietal.2021, author = {Kremer, Naomi I. and Pauwels, Rik W. J. and Pozzi, Nicol{\`o} G. and Lange, Florian and Roothans, Jonas and Volkmann, Jens and Reich, Martin M.}, title = {Deep Brain Stimulation for Tremor: Update on Long-Term Outcomes, Target Considerations and Future Directions}, series = {Journal of Clinical Medicine}, volume = {10}, journal = {Journal of Clinical Medicine}, number = {16}, issn = {2077-0383}, doi = {10.3390/jcm10163468}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244982}, year = {2021}, abstract = {Deep brain stimulation (DBS) of the thalamic ventral intermediate nucleus is one of the main advanced neurosurgical treatments for drug-resistant tremor. However, not every patient may be eligible for this procedure. Nowadays, various other functional neurosurgical procedures are available. In particular cases, radiofrequency thalamotomy, focused ultrasound and radiosurgery are proven alternatives to DBS. Besides, other DBS targets, such as the posterior subthalamic area (PSA) or the dentato-rubro-thalamic tract (DRT), may be appraised as well. In this review, the clinical characteristics and pathophysiology of tremor syndromes, as well as long-term outcomes of DBS in different targets, will be summarized. The effectiveness and safety of lesioning procedures will be discussed, and an evidence-based clinical treatment approach for patients with drug-resistant tremor will be presented. Lastly, the future directions in the treatment of severe tremor syndromes will be elaborated.}, language = {en} }