@article{BreyerGruenerKleinetal.2024, author = {Breyer, Maximilian and Gr{\"u}ner, Julia and Klein, Alexandra and Finke, Laura and Klug, Katharina and Sauer, Markus and {\"U}{\c{c}}eyler, Nurcan}, title = {\(In\) \(vitro\) characterization of cells derived from a patient with the GLA variant c.376A>G (p.S126G) highlights a non-pathogenic role in Fabry disease}, series = {Molecular Genetics and Metabolism Reports}, volume = {38}, journal = {Molecular Genetics and Metabolism Reports}, issn = {22144269}, doi = {10.1016/j.ymgmr.2023.101029}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350295}, year = {2024}, abstract = {Highlights • The GLA variant S126G is not associated with Fabry symptoms in the presented case • S126G has no effect on α-GAL A activity or Gb3 levels in this patient • S126G sensory neurons show no electrophysiological abnormalities Abstract Fabry disease (FD) is a life-limiting disorder characterized by intracellular globotriaosylceramide (Gb3) accumulations. The underlying α-galactosidase A (α-GAL A) deficiency is caused by variants in the gene GLA. Variants of unknown significance (VUS) are frequently found in GLA and challenge clinical management. Here, we investigated a 49-year old man with cryptogenic lacunar cerebral stroke and the chance finding of the VUS S126G, who was sent to our center for diagnosis and initiation of a costly and life-long FD-specific treatment. We combined clinical examination with in vitro investigations of dermal fibroblasts (HDF), induced pluripotent stem cells (iPSC), and iPSC-derived sensory neurons. We analyzed α-GAL A activity in iPSC, Gb3 accumulation in all three cell types, and action potential firing in sensory neurons. Neurological examination and small nerve fiber assessment was normal except for reduced distal skin innervation. S126G iPSC showed normal α-GAL A activity compared to controls and no Gb3 deposits were found in all three cell types. Baseline electrophysiological characteristics of S126G neurons showed no difference compared to healthy controls as investigated by patch-clamp recordings. We pioneer multi-level cellular characterization of the VUS S126G using three cell types derived from a patient and provide further evidence for the benign nature of S126G in GLA, which is of great importance in the management of such cases in clinical practice.}, language = {en} } @article{JaenschEvdokimovEgenolfetal.2024, author = {J{\"a}nsch, Sarah and Evdokimov, Dimitar and Egenolf, Nadine and Meyer zu Altenschildesche, Caren and Kreß, Luisa and {\"U}{\c{c}}eyler, Nurcan}, title = {Distinguishing fibromyalgia syndrome from small fiber neuropathy: a clinical guide}, series = {Pain Reports}, volume = {9}, journal = {Pain Reports}, number = {1}, doi = {10.1097/PR9.0000000000001136}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350306}, year = {2024}, abstract = {Introduction: Fibromyalgia syndrome (FMS) and small fiber neuropathy (SFN) are distinct pain conditions that share commonalities and may be challenging as for differential diagnosis. Objective: To comprehensively investigate clinical characteristics of women with FMS and SFN to determine clinically applicable parameters for differentiation. Methods: We retrospectively analyzed medical records of 158 women with FMS and 53 with SFN focusing on pain-specific medical and family history, accompanying symptoms, additional diseases, and treatment. We investigated data obtained using standardized pain, depression, and anxiety questionnaires. We further analyzed test results and findings obtained in standardized small fiber tests. Results: FMS patients were on average ten years younger at symptom onset, described higher pain intensities requiring frequent change of pharmaceutics, and reported generalized pain compared to SFN. Pain in FMS was accompanied by irritable bowel or sleep disturbances, and in SFN by paresthesias, numbness, and impaired glucose metabolism (P < 0.01 each). Family history was informative for chronic pain and affective disorders in FMS (P < 0.001) and for neurological disorders in SFN patients (P < 0.001). Small fiber pathology in terms of skin denervation and/or thermal sensory threshold elevation was present in 110/158 (69.7 \%) FMS patients and 39/53 (73.6 \%) SFN patients. FMS patients mainly showed proximally reduced skin innervation and higher corneal nerve branch densities (p<0.001) whereas SFN patients were characterized by reduced cold detection and prolonged electrical A-delta conduction latencies (P < 0.05). Conclusions: Our data show that FMS and SFN differ substantially. Detailed pain, drug and family history, investigating blood glucose metabolism, and applying differential small fiber tests may help to improve diagnostic differentiation and targeted therapy.}, language = {en} } @article{KressEgenolfSommeretal.2023, author = {Kreß, Luisa and Egenolf, Nadine and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Cytokine expression profiles in white blood cells of patients with small fiber neuropathy}, series = {BMC Neuroscience}, volume = {24}, journal = {BMC Neuroscience}, number = {1}, doi = {10.1186/s12868-022-00770-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300619}, year = {2023}, abstract = {Background The role of cytokines in the pathophysiology, diagnosis, and prognosis of small fiber neuropathy (SFN) is incompletely understood. We studied expression profiles of selected pro- and anti-inflammatory cytokines in RNA from white blood cells (WBC) of patients with a medical history and a clinical phenotype suggestive for SFN and compared data with healthy controls. Methods We prospectively recruited 52 patients and 21 age- and sex-matched healthy controls. Study participants were characterized in detail and underwent complete neurological examination. Venous blood was drawn for routine and extended laboratory tests, and for WBC isolation. Systemic RNA expression profiles of the pro-inflammatory cytokines interleukin (IL)-1ß, IL-2, IL-8, tumor necrosis factor-alpha (TNF) and the anti-inflammatory cytokines IL-4, IL-10, transforming growth factor beta-1 (TGF) were analyzed. Protein levels of IL-2, IL-8, and TNF were measured in serum of patients and controls. Receiver operating characteristic (ROC)-curve analysis was used to determine the accuracy of IL-2, IL-8, and TNF in differentiating patients and controls. To compare the potential discriminatory efficacy of single versus combined cytokines, equality of different AUCs was tested. Results WBC gene expression of IL-2, IL-8, and TNF was higher in patients compared to healthy controls (IL-2: p = 0.02; IL-8: p = 0.009; TNF: p = 0.03) and discriminated between the groups (area under the curve (AUC) ≥ 0.68 for each cytokine) with highest diagnostic accuracy reached by combining the three cytokines (AUC = 0.81, sensitivity = 70\%, specificity = 86\%). Subgroup analysis revealed the following differences: IL-8 and TNF gene expression levels were higher in female patients compared to female controls (IL-8: p = 0.01; TNF: p = 0.03). The combination of TNF with IL-2 and TNF with IL-2 and IL-8 discriminated best between the study groups. IL-2 was higher expressed in patients with moderate pain compared to those with severe pain (p = 0.02). Patients with acral pain showed higher IL-10 gene expression compared to patients with generalized pain (p = 0.004). We further found a negative correlation between the relative gene expression of IL-2 and current pain intensity (p = 0.02). Serum protein levels of IL-2, IL-8, and TNF did not differ between patients and controls. Conclusions We identified higher systemic gene expression of IL-2, IL-8, and TNF in SFN patients than in controls, which may be of potential relevance for diagnostics and patient stratification.}, language = {en} } @article{GarciaFernandezReinholdUeceyleretal.2023, author = {Garc{\´i}a-Fern{\´a}ndez, Patricia and Reinhold, Colette and {\"U}{\c{c}}eyler, Nurcan and Sommer, Claudia}, title = {Local inflammatory mediators involved in neuropathic pain}, series = {International Journal of Molecular Sciences}, volume = {24}, journal = {International Journal of Molecular Sciences}, number = {9}, issn = {1422-0067}, doi = {10.3390/ijms24097814}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313613}, year = {2023}, abstract = {Polyneuropathy (PNP) is a term to describe diseases of the peripheral nervous system, 50\% of which present with neuropathic pain. In some types of PNP, pain is restricted to the skin distally in the leg, suggesting a local regulatory process leading to pain. In this study, we proposed a pro-inflammatory pathway mediated by NF-κB that might be involved in the development of pain in patients with painful PNP. To test this hypothesis, we have collected nerve and skin samples from patients with different etiologies and levels of pain. We performed RT-qPCR to analyze the gene expression of the proposed inflammatory pathway components in sural nerve and in distal and proximal skin samples. In sural nerve, we showed a correlation of TLR4 and TNFα to neuropathic pain, and an upregulation of TNFα in patients with severe pain. Patients with an inflammatory PNP also presented a lower expression of TRPV1 and SIRT1. In distal skin, we found a reduced expression of TLR4 and miR-146-5p, in comparison to proximal skin. Our findings thus support our hypothesis of local inflammatory processes involved in pain in PNP, and further show disturbed anti-inflammatory pathways involving TRPV1 and SIRT1 in inflammatory PNP.}, language = {en} } @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{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{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{UeceylerSchliesserEvdokimovetal.2022, author = {{\"U}{\c{c}}eyler, Nurcan and Schließer, Mira and Evdokimov, Dimitar and Radziwon, Jakub and Feulner, Betty and Unterecker, Stefan and Rimmele, Florian and Walter, Uwe}, title = {Reduced midbrain raphe echogenicity in patients with fibromyalgia syndrome}, series = {PloS One}, volume = {17}, journal = {PloS One}, number = {11}, doi = {10.1371/journal.pone.0277316}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300639}, year = {2022}, abstract = {Objectives The pathogenesis of fibromyalgia syndrome (FMS) is unclear. Transcranial ultrasonography revealed anechoic alteration of midbrain raphe in depression and anxiety disorders, suggesting affection of the central serotonergic system. Here, we assessed midbrain raphe echogenicity in FMS. Methods Sixty-six patients underwent transcranial sonography, of whom 53 were patients with FMS (27 women, 26 men), 13 patients with major depression and physical pain (all women), and 14 healthy controls (11 women, 3 men). Raphe echogenicity was graded visually as normal or hypoechogenic, and quantified by digitized image analysis, each by investigators blinded to the clinical diagnosis. Results Quantitative midbrain raphe echogenicity was lower in patients with FMS compared to healthy controls (p<0.05), but not different from that of patients with depression and accompanying physical pain. Pain and FMS symptom burden did not correlate with midbrain raphe echogenicity as well as the presence and severity of depressive symptoms. Conclusion We found reduced echogenicity of the midbrain raphe area in patients with FMS and in patients with depression and physical pain, independent of the presence or severity of pain, FMS, and depressive symptoms. Further exploration of this sonographic finding is necessary before this objective technique may enter diagnostic algorithms in FMS and depression.}, language = {en} } @article{SchosseeVeitGitteletal.2022, author = {Schossee, Nadine and Veit, Gabriele and Gittel, Julia and Viebahn, Johannes and Niklaus, Marius and Klingler, Philipp and {\"U}{\c{c}}eyler, Nurcan and Klinker, Erdwine and Kobsar, Anna and Boeck, Markus and Koessler, Juergen}, title = {Profile of the single-use, multiple-pass protein A adsorber column in immunoadsorption}, series = {Vox Sanguinis}, volume = {117}, journal = {Vox Sanguinis}, number = {3}, doi = {10.1111/vox.13205}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259689}, pages = {393-398}, year = {2022}, abstract = {Background and Objectives Immunoadsorptions (IA) are used to remove autoantibodies from the plasma in autoimmune disorders. In this study, we evaluated the effects of a single-use, recombinant staphylococcal protein A-based immunoadsorber on blood composition of the patient. Materials and Methods In a cohort of patients with myasthenia gravis or stiff-person syndrome, essential parameters of blood cell count, coagulation, clinical chemistry or plasma proteins and immunoglobulins (Ig) were measured before and after IA (n = 11). Results In average, IA reduced the levels of total IgG, IgG1, IgG2 and IgG4 by approximately 60\%, the acetylcholine receptor autoantibody levels by more than 70\%. IgG3, IgA or IgM were diminished to a lower extent. In contrast to fibrinogen or other coagulation factors, the column markedly removed vitamin K-dependent coagulation factors II, VII, IX and X by approximately 40\%-70\%. Accordingly, international normalized ratio and activated partial thromboplastin time were increased after IA by 59.1\% and 32.7\%, respectively. Coagulation tests almost returned to baseline values within 24 h. Blood cell count, electrolytes, total protein or albumin were not essentially affected. No clinical events occurred. Conclusion The single-use, multiple-pass protein A adsorber column is highly efficient to remove IgG1, IgG2 and IgG4 or specific acetylcholine receptor autoantibodies from the plasma. Coagulation parameters should be monitored, since the column has the capacity to largely reduce vitamin K-dependent factors.}, language = {en} }