@article{OezdağAcarlıKleinEgenolfetal.2022, author = {{\"O}zdağ Acarl{\i}, Ay{\c{s}}e Nur and Klein, Thomas and Egenolf, Nadine and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Subepidermal Schwann cell counts correlate with skin innervation - an exploratory study}, series = {Muscle \& Nerve}, volume = {65}, journal = {Muscle \& Nerve}, number = {4}, doi = {10.1002/mus.27496}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318726}, pages = {471 -- 479}, year = {2022}, abstract = {Introduction/Aims Schwann cell clusters have been described at the murine dermis-epidermis border. We quantified dermal Schwann cells in the skin of patients with small-fiber neuropathy (SFN) compared with healthy controls to correlate with the clinical phenotype. Methods Skin punch biopsies from the lower legs of 28 patients with SFN (11 men, 17 women; median age, 54 [range, 19-73] years) and 9 healthy controls (five men, four women, median age, 34 [range, 25-69] years) were immunoreacted for S100 calcium-binding protein B as a Schwann cell marker, protein-gene product 9.5 as a pan-neuronal marker, and CD207 as a Langerhans cell marker. Intraepidermal nerve fiber density (IENFD) and subepidermal Schwann cell counts were determined. Results Skin samples of patients with SFN showed lower IENFD (P < .05), fewer Schwann cells per millimeter (P < .01), and fewer Schwann cell clusters per millimeter (P < .05) than controls. When comparing SFN patients with reduced (n = 13; median age, 53 [range, 19-73] years) and normal distal (n = 15, median age, 54 [range, 43-68] years) IENFD, the number of solitary Schwann cells per millimeter (p < .01) and subepidermal nerve fibers associated with Schwann cell branches (P < .05) were lower in patients with reduced IENFD. All three parameters correlated positively with distal IENFD (P < .05 to P < .01), whereas no correlation was found between Schwann cell counts and clinical pain characteristics. Discussion Our data raise questions about the mechanisms underlying the interdependence of dermal Schwann cells and skin innervation in SFN. The temporal course and functional impact of Schwann cell presence and kinetics need further investigation.}, language = {en} } @article{Sommer2022, author = {Sommer, Claudia}, title = {Natural course of Guillain-Barr{\´e} syndrome}, series = {European Journal of Neurology}, volume = {29}, journal = {European Journal of Neurology}, number = {10}, doi = {10.1111/ene.15498}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318757}, pages = {2881 -- 2882}, year = {2022}, language = {en} } @article{AsterEvdokimovBraunetal.2022, author = {Aster, Hans-Christoph and Evdokimov, Dimitar and Braun, Alexandra and {\"U}{\c{c}}eyler, Nurcan and Kampf, Thomas and Pham, Mirko and Homola, Gy{\"o}rgy A. and Sommer, Claudia}, title = {CNS imaging characteristics in fibromyalgia patients with and without peripheral nerve involvement}, series = {Scientific Reports}, volume = {12}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-022-10489-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300562}, year = {2022}, abstract = {We tested the hypothesis that reduced skin innervation in fibromyalgia syndrome is associated with specific CNS changes. This prospective case-control study included 43 women diagnosed with fibromyalgia syndrome and 40 healthy controls. We further compared the fibromyalgia subgroups with reduced (n = 21) and normal (n = 22) skin innervation. Brains were analysed for cortical volume, for white matter integrity, and for functional connectivity. Compared to controls, cortical thickness was decreased in regions of the frontal, temporal and parietal cortex in the fibromyalgia group as a whole, and decreased in the bilateral pericalcarine cortices in the fibromyalgia subgroup with reduced skin innervation. Diffusion tensor imaging revealed a significant increase in fractional anisotropy in the corona radiata, the corpus callosum, cingulum and fornix in patients with fibromyalgia compared to healthy controls and decreased FA in parts of the internal capsule and thalamic radiation in the subgroup with reduced skin innervation. Using resting-state fMRI, the fibromyalgia group as a whole showed functional hypoconnectivity between the right midfrontal gyrus and the posterior cerebellum and the right crus cerebellum, respectively. The subgroup with reduced skin innervation showed hyperconnectivity between the inferior frontal gyrus, the angular gyrus and the posterior parietal gyrus. Our results suggest that the subgroup of fibromyalgia patients with pronounced pathology in the peripheral nervous system shows alterations in morphology, structural and functional connectivity also at the level of the encephalon. We propose considering these subgroups when conducting clinical trials.}, language = {en} } @article{ReinholdKrugSalvadoretal.2022, author = {Reinhold, Ann Kristin and Krug, Susanne M. and Salvador, Ellaine and Sauer, Reine S. and Karl-Sch{\"o}ller, Franziska and Malcangio, Marzia and Sommer, Claudia and Rittner, Heike L.}, title = {MicroRNA-21-5p functions via RECK/MMP9 as a proalgesic regulator of the blood nerve barrier in nerve injury}, series = {Annals of the New York Academy of Sciences}, volume = {1515}, journal = {Annals of the New York Academy of Sciences}, number = {1}, doi = {10.1111/nyas.14816}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318226}, pages = {184 -- 195}, year = {2022}, abstract = {Both nerve injury and complex regional pain syndrome (CRPS) can result in chronic pain. In traumatic neuropathy, the blood nerve barrier (BNB) shielding the nerve is impaired—partly due to dysregulated microRNAs (miRNAs). Upregulation of microRNA-21-5p (miR-21) has previously been documented in neuropathic pain, predominantly due to its proinflammatory features. However, little is known about other functions. Here, we characterized miR-21 in neuropathic pain and its impact on the BNB in a human-murine back translational approach. MiR-21 expression was elevated in plasma of patients with CRPS as well as in nerves of mice after transient and persistent nerve injury. Mice presented with BNB leakage, as well as loss of claudin-1 in both injured and spared nerves. Moreover, the putative miR-21 target RECK was decreased and downstream Mmp9 upregulated, as was Tgfb. In vitro experiments in human epithelial cells confirmed a downregulation of CLDN1 by miR-21 mimics via inhibition of the RECK/MMP9 pathway but not TGFB. Perineurial miR-21 mimic application in mice elicited mechanical hypersensitivity, while local inhibition of miR-21 after nerve injury reversed it. In summary, the data support a novel role for miR-21, independent of prior inflammation, in elicitation of pain and impairment of the BNB via RECK/MMP9.}, language = {en} } @article{WagenhaeuserRickertSommeretal.2022, author = {Wagenh{\"a}user, Laura and Rickert, Vanessa and Sommer, Claudia and Wanner, Christoph and Nordbeck, Peter and Rost, Simone and {\"U}{\c{c}}eyler, Nurcan}, title = {X-chromosomal inactivation patterns in women with Fabry disease}, series = {Molecular Genetics \& Genomic Medicine}, volume = {10}, journal = {Molecular Genetics \& Genomic Medicine}, number = {9}, doi = {10.1002/mgg3.2029}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312795}, year = {2022}, abstract = {Background Although Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the α-galactosidase A gene (GLA), women may develop severe symptoms. We investigated X-chromosomal inactivation patterns (XCI) as a potential determinant of symptom severity in FD women. Patients and Methods We included 95 women with mutations in GLA (n = 18 with variants of unknown pathogenicity) and 50 related men, and collected mouth epithelial cells, venous blood, and skin fibroblasts for XCI analysis using the methylation status of the androgen receptor gene. The mutated X-chromosome was identified by comparison of samples from relatives. Patients underwent genotype categorization and deep clinical phenotyping of symptom severity. Results 43/95 (45\%) women carried mutations categorized as classic. The XCI pattern was skewed (i.e., ≥75:25\% distribution) in 6/87 (7\%) mouth epithelial cell samples, 31/88 (35\%) blood samples, and 9/27 (33\%) skin fibroblast samples. Clinical phenotype, α-galactosidase A (GAL) activity, and lyso-Gb3 levels did not show intergroup differences when stratified for X-chromosomal skewing and activity status of the mutated X-chromosome. Conclusions X-inactivation patterns alone do not reliably reflect the clinical phenotype of women with FD when investigated in biomaterial not directly affected by FD. However, while XCI patterns may vary between tissues, blood frequently shows skewing of XCI patterns.}, language = {en} } @article{SpitzelWagnerBreyeretal.2022, author = {Spitzel, Marlene and Wagner, Elise and Breyer, Maximilian and Henniger, Dorothea and Bayin, Mehtap and Hofmann, Lukas and Mauceri, Daniela and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Dysregulation of immune response mediators and pain-related ion channels is associated with pain-like behavior in the GLA KO mouse model of Fabry disease}, series = {Cells}, volume = {11}, journal = {Cells}, number = {11}, issn = {2073-4409}, doi = {10.3390/cells11111730}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-275186}, year = {2022}, abstract = {Fabry disease (FD) is a rare life-threatening disorder caused by deficiency of the alpha-galactosidase A (GLA) enzyme with a characteristic pain phenotype. Impaired GLA production or function leads to the accumulation of the cell membrane compound globotriaosylceramide (Gb3) in the neurons of the dorsal root ganglia (DRG) of FD patients. Applying immunohistochemistry (IHC) and quantitative real-time polymerase chain reaction (qRT PCR) analysis on DRG tissue of the GLA knockout (KO) mouse model of FD, we address the question of how Gb3 accumulation may contribute to FD pain and focus on the immune system and pain-associated ion channel gene expression. We show a higher Gb3 load in the DRG of young (<6 months) (p < 0.01) and old (≥12 months) (p < 0.001) GLA KO mice compared to old wildtype (WT) littermates, and an overall suppressed immune response in the DRG of old GLA KO mice, represented by a reduced number of CD206\(^+\) macrophages (p < 0.01) and lower gene expression levels of the inflammation-associated targets interleukin(IL)1b (p < 0.05), IL10 (p < 0.001), glial fibrillary acidic protein (GFAP) (p < 0.05), and leucine rich alpha-2-glycoprotein 1 (LRG1) (p < 0.01) in the DRG of old GLA KO mice compared to old WT. Dysregulation of immune-related genes may be linked to lower gene expression levels of the pain-associated ion channels calcium-activated potassium channel 3.1 (KCa3.1) and transient receptor potential ankyrin 1 channel (TRPA1). Ion channel expression might further be disturbed by impaired sphingolipid recruitment mediated via the lipid raft marker flotillin-1 (FLOT1). This impairment is represented by an increased number of FLOT1\(^+\) DRG neurons with a membranous expression pattern in old GLA KO mice compared to young GLA KO, young WT, and old WT mice (p < 0.001 each). Further, we provide evidence for aberrant behavior of GLA KO mice, which might be linked to dysregulated ion channel gene expression levels and disturbed FLOT1 distribution patterns. Behavioral testing revealed mechanical hypersensitivity in young (p < 0.01) and old (p < 0.001) GLA KO mice compared to WT, heat hypersensitivity in young GLA KO mice (p < 0.001) compared to WT, age-dependent heat hyposensitivity in old GLA KO mice (p < 0.001) compared to young GLA KO mice, and cold hyposensitivity in young (p < 0.001) and old (p < 0.001) GLA KO mice compared to WT, which well reflects the clinical phenotype observed in FD patients.}, language = {en} } @article{BraunEvdokimovFranketal.2022, author = {Braun, Alexandra and Evdokimov, Dimitar and Frank, Johanna and Pauli, Paul and Wabel, Thomas and {\"U}{\c{c}}eyler, Nurcan and Sommer, Claudia}, title = {Relevance of Religiosity for Coping Strategies and Disability in Patients with Fibromyalgia Syndrome}, series = {Journal of Religion and Health}, volume = {61}, journal = {Journal of Religion and Health}, number = {1}, issn = {1573-6571}, doi = {10.1007/s10943-020-01177-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-269135}, pages = {524-539}, year = {2022}, abstract = {Coping strategies are essential for the outcome of chronic pain. This study evaluated religiosity in a cohort of patients with fibromyalgia syndrome (FMS), its effect on pain and other symptoms, on coping and FMS-related disability. A total of 102 FMS patients were recruited who filled in questionnaires, a subgroup of 42 patients participated in a face-to-face interview, and data were evaluated by correlation and regression analyses. Few patients were traditionally religious, but the majority believed in a higher existence and described their spirituality as "transcendence conviction". The coping strategy "praying-hoping" and the ASP dimension "religious orientation" (r = 0.5, P < 0.05) showed a significant relationship independent of the grade of religiosity (P < 0.05). A high grade of belief in a higher existence was negatively associated with the choice of ignoring as coping strategy (r = - 0.4, P < 0.05). Mood and affect-related variables had the highest impact on disability (b = 0.5, P < 0.05). In this cohort, the grade of religiosity played a role in the choice of coping strategies, but had no effects on health and mood outcome.}, language = {en} } @article{LauUeceylerCairnsetal.2022, author = {Lau, Kolja and {\"U}{\c{c}}eyler, Nurcan and Cairns, Tereza and Lorenz, Lora and Sommer, Claudia and Schindeh{\"u}tte, Magnus and Amann, Kerstin and Wanner, Christoph and Nordbeck, Peter}, title = {Gene variants of unknown significance in Fabry disease: Clinical characteristics of c.376AG (p.Ser126Gly)}, series = {Molecular Genetics \& Genomic Medicine}, volume = {10}, journal = {Molecular Genetics \& Genomic Medicine}, number = {5}, doi = {10.1002/mgg3.1912}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312817}, year = {2022}, abstract = {Background Anderson-Fabry disease (FD) is an X-linked lysosomal storage disorder with varying organ involvement and symptoms, depending on the underlying mutation in the alpha-galactosidase A gene (HGNC: GLA). With genetic testing becoming more readily available, it is crucial to precisely evaluate pathogenicity of each genetic variant, in order to determine whether there is or might be not a need for FD-specific therapy in affected patients and relatives at the time point of presentation or in the future. Methods This case series investigates the clinical impact of the specific GLA gene variant c.376A>G (p.Ser126Gly) in five (one heterozygous and one homozygous female, three males) individuals from different families, who visited our center between 2009 and 2021. Comprehensive neurological, nephrological and cardiac examinations were performed in all cases. One patient received a follow-up examination after 12 years. Results Index events leading to suspicion of FD were mainly unspecific neurological symptoms. However, FD-specific biomarkers, imaging examinations (i.e., brain MRI, heart MRI), and tissue-specific diagnostics, including kidney and skin biopsies, did not reveal evidence for FD-specific symptoms or organ involvement but showed normal results in all cases. This includes findings from 12-year follow-up in one patient with renal biopsy. Conclusion These findings suggest that p.Ser126Gly represents a benign GLA gene variant which per se does not cause FD. Precise clinical evaluation in individuals diagnosed with genetic variations of unknown significance should be performed to distinguish common symptoms broadly prevalent in the general population from those secondary to FD.}, language = {en} } @article{ErbacherVaknineMoshitzkyetal.2022, author = {Erbacher, Christoph and Vaknine, Shani and Moshitzky, Gilli and Lobentanzer, Sebastian and Eisenberg, Lina and Evdokimov, Dimitar and Sommer, Claudia and Greenberg, David S. and Soreq, Hermona and {\"U}{\c{c}}eyler, Nurcan}, title = {Distinct CholinomiR blood cell signature as a potential modulator of the cholinergic system in women with fibromyalgia syndrome}, series = {Cells}, volume = {11}, journal = {Cells}, number = {8}, issn = {2073-4409}, doi = {10.3390/cells11081276}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270686}, year = {2022}, abstract = {Fibromyalgia syndrome (FMS) is a heterogeneous chronic pain syndrome characterized by musculoskeletal pain and other key co-morbidities including fatigue and a depressed mood. FMS involves altered functioning of the central and peripheral nervous system (CNS, PNS) and immune system, but the specific molecular pathophysiology remains unclear. Anti-cholinergic treatment is effective in FMS patient subgroups, and cholinergic signaling is a strong modulator of CNS and PNS immune processes. Therefore, we used whole blood small RNA-sequencing of female FMS patients and healthy controls to profile microRNA regulators of cholinergic transcripts (CholinomiRs). We compared microRNA profiles with those from Parkinson's disease (PD) patients with pain as disease controls. We validated the sequencing results with quantitative real-time PCR (qRT-PCR) and identified cholinergic targets. Further, we measured serum cholinesterase activity in FMS patients and healthy controls. Small RNA-sequencing revealed FMS-specific changes in 19 CholinomiRs compared to healthy controls and PD patients. qRT-PCR validated miR-182-5p upregulation, distinguishing FMS patients from healthy controls. mRNA targets of CholinomiRs bone morphogenic protein receptor 2 and interleukin 6 signal transducer were downregulated. Serum acetylcholinesterase levels and cholinesterase activity in FMS patients were unchanged. Our findings identified an FMS-specific CholinomiR signature in whole blood, modulating immune-related gene expression.}, language = {en} } @article{AppeltshauserMessingerStarzetal.2022, author = {Appeltshauser, Luise and Messinger, Julia and Starz, Katharina and Heinrich, David and Brunder, Anna-Michelle and Stengel, Helena and Fiebig, Bianca and Ayzenberg, Ilya and Birklein, Frank and Dresel, Christian and Dorst, Johannes and Dvorak, Florian and Grimm, Alexander and Joerk, Alexander and Leypoldt, Frank and M{\"a}urer, Mathias and Merl, Patrick and Michels, Sebastian and Pitarokoili, Kalliopi and Rosenfeldt, Mathias and Sperfeld, Anne-Dorte and Weihrauch, Marc and Welte, Gabriel Simon and Sommer, Claudia and Doppler, Kathrin}, title = {Diabetes Mellitus Is a Possible Risk Factor for Nodo-paranodopathy With Antiparanodal Autoantibodies}, series = {Neurology: Neuroimmunology \& Neuroinflammation}, volume = {9}, journal = {Neurology: Neuroimmunology \& Neuroinflammation}, number = {3}, doi = {10.1212/NXI.0000000000001163}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300551}, year = {2022}, abstract = {Background and Objectives Nodo-paranodopathies are peripheral neuropathies with dysfunction of the node of Ranvier. Affected patients who are seropositive for antibodies against adhesion molecules like contactin-1 and neurofascin show distinct clinical features and a disruption of the paranodal complex. An axoglial dysjunction is also a characteristic finding of diabetic neuropathy. Here, we aim to investigate a possible association of antibody-mediated nodo-paranodopathy and diabetes mellitus (DM). Methods We retrospectively analyzed clinical data of 227 patients with chronic inflammatory demyelinating polyradiculoneuropathy and Guillain-Barr{\´e} syndrome from multiple centers in Germany who had undergone diagnostic testing for antiparanodal antibodies targeting neurofascin-155, pan-neurofascin, contactin-1-associated protein 1, and contactin-1. To study possible direct pathogenic effects of antiparanodal antibodies, we performed immunofluorescence binding assays on human pancreatic tissue sections. Results The frequency of DM was 33.3\% in seropositive patients and thus higher compared with seronegative patients (14.1\%, OR = 3.04, 95\% CI = 1.31-6.80). The relative risk of DM in seropositive patients was 3.4-fold higher compared with the general German population. Seropositive patients with DM most frequently harbored anti-contactin-1 antibodies and had higher antibody titers than seropositive patients without DM. The diagnosis of DM preceded the onset of neuropathy in seropositive patients. No immunoreactivity of antiparanodal antibodies against pancreatic tissue was detected. Discussion We report an association of nodo-paranodopathy and DM. Our results suggest that DM may be a potential risk factor for predisposing to developing nodo-paranodopathy and argue against DM being induced by the autoantibodies. Our findings set the basis for further research investigating underlying immunopathogenetic connections.}, language = {en} }