TY - JOUR A1 - Üçeyler, Nurcan A1 - Kewenig, Susanne A1 - Kittel-Schneider, Sarah A1 - Fallgatter, Andreas J. A1 - Sommer, Claudia T1 - Increased cortical activation upon painful stimulation in fibromyalgia syndrome JF - BMC Neurology N2 - Background Fibromyalgia syndrome (FMS) is a chronic condition characterized by widespread pain and associated symptoms. We investigated cerebral activation in FMS patients by functional near-infrared spectroscopy (fNIRS). Methods Two stimulation paradigms were applied: a) painful pressure stimulation at the dorsal forearm; b) verbal fluency test (VFT). We prospectively recruited 25 FMS patients, ten patients with unipolar major depression (MD) without pain, and 35 healthy controls. All patients underwent neurological examination and all subjects were investigated with questionnaires (pain, depression, FMS, empathy). Results FMS patients had lower pressure pain thresholds than patients with MD and controls (p < 0.001) and reported higher pain intensity (p < 0.001). Upon unilateral pressure pain stimulation fNIRS recordings revealed increased bilateral cortical activation in FMS patients compared to controls (p < 0.05). FMS patients also displayed a stronger contralateral activity over the dorsolateral prefrontal cortex in direct comparison to patients with MD (p < 0.05). While all three groups performed equally well in the VFT, a frontal deficit in cortical activation was only found in patients with depression (p < 0.05). Performance and cortical activation correlated negatively in FMS patients (p < 0.05) and positively in patients with MD (p < 0.05). Conclusion Our data give further evidence for altered central nervous processing in patients with FMS and the distinction between FMS and MD. KW - fibromyalgia syndrome KW - depression KW - cortical activation KW - pain KW - near-infrared spectroscopy Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125230 VL - 15 IS - 210 ER - TY - JOUR A1 - Hansen, Niels A1 - Kahn, Ann-Kathrin A1 - Zeller, Daniel A1 - Katsarava, Zaza A1 - Sommer, Claudia A1 - Üçeyler, Nurcan T1 - Amplitudes of pain-related evoked potentials are useful to detect small fiber involvement in painful mixed fiber neuropathies in addition to quantitative sensory testing – an electrophysiological study JF - Frontiers in Neurology N2 - To investigate the usefulness of pain-related evoked potentials (PREP) elicited by electrical stimulation for the identification of small fiber involvement in patients with mixed fiber neuropathy (MFN). Eleven MFN patients with clinical signs of large fiber impairment and neuropathic pain and ten healthy controls underwent clinical and electrophysiological evaluation. Small fiber function, electrical conductivity and morphology were examined by quantitative sensory testing (QST), PREP, and skin punch biopsy. MFN was diagnosed following clinical and electrophysiological examination (chronic inflammatory demyelinating neuropathy: n = 6; vasculitic neuropathy: n = 3; chronic axonal ­neuropathy: n = 2). The majority of patients with MFN characterized their pain by descriptors that mainly represent C-fiber-mediated pain. In QST, patients displayed elevated cold, warm, mechanical, and vibration detection thresholds and cold pain thresholds indicative of MFN. PREP amplitudes in patients correlated with cold (p < 0.05) and warm detection thresholds (p < 0.05). Burning pain and the presence of par-/dysesthesias correlated negatively with PREP amplitudes (p < 0.05). PREP amplitudes correlating with cold and warm detection thresholds, burning pain, and par-/dysesthesias support employing PREP amplitudes as an additional tool in conjunction with QST for detecting small fiber impairment in patients with MFN. KW - burning pain KW - quantitative sensory testing KW - mixed fiber neuropathy KW - pain-related evoked potentials KW - Aδ- and C-fibers KW - neuropathic pain Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124824 VL - 6 ER - TY - JOUR A1 - Puschmann, Anne-Katrin A1 - Sommer, Claudia T1 - Hypervigilance or avoidance of trigger related cues in migraineurs? - A case-control study using the emotional stroop task JF - BMC Neurology N2 - Background "Negative affect" is one of the major migraine triggers. The aim of the study was to assess attentional biases for negative affective stimuli that might be related to migraine triggers in migraine patients with either few or frequent migraine and healthy controls. Methods Thirty-three subjects with frequent migraine (FM) or with less frequent episodic migraine, and 20 healthy controls conducted two emotional Stroop tasks in the interictal period. In task 1, general affective words and in task 2, pictures of affective faces (angry, neutral, happy) were used. For each task we calculated two emotional Stroop indices. Groups were compared using one-way ANOVAs. Results The expected attentional bias in migraine patients was not found. However, in task 2 the controls showed a significant attentional bias to negative faces, whereas the FM group showed indices near zero. Thus, the FM group responded faster to negative than to positive stimuli. The difference between the groups was statistically significant. Conclusions The findings in the FM group may reflect a learned avoidance mechanism away from affective migraine triggers. KW - migraineur KW - cue Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137750 VL - 11 IS - 141 ER - TY - JOUR A1 - Üçeyler, Nurcan A1 - Topuzoğlu, Tengü A1 - Schießer, Peter A1 - Hahnenkamp, Saskia A1 - Sommer, Claudia T1 - IL-4 Deficiency Is Associated with Mechanical Hypersensitivity in Mice JF - PLoS One N2 - Interleukin-4 (IL-4) is an anti-inflammatory and analgesic cytokine that induces opioid receptor transcription. We investigated IL-4 knockout (ko) mice to characterize their pain behavior before and after chronic constriction injury (CCI) of the sciatic nerve as a model for neuropathic pain. We investigated opioid responsivity and measured cytokine and opioid receptor gene expression in the peripheral and central nervous system (PNS, CNS) of IL-4 ko mice in comparison with wildtype (wt) mice. Naïve IL-4 ko mice displayed tactile allodynia (wt: 0.45 g; ko: 0.18 g; p<0.001), while responses to heat and cold stimuli and to muscle pressure were not different. No compensatory changes in the gene expression of tumor necrosis factor-alpha (TNF), IL-1β, IL-10, and IL-13 were found in the PNS and CNS of naïve IL-4 ko mice. However, IL-1β gene expression was stronger in the sciatic nerve of IL-4 ko mice (p<0.001) 28 days after CCI and only IL-4 ko mice had elevated IL-10 gene expression (p = 0.014). Remarkably, CCI induced TNF (p<0.01), IL-1β (p<0.05), IL-10 (p<0.05), and IL-13 (p<0.001) gene expression exclusively in the ipsilateral spinal cord of IL-4 ko mice. The compensatory overexpression of the anti-inflammatory and analgesic cytokines IL-10 and IL-13 in the spinal cord of IL-4 ko mice may explain the lack of genotype differences for pain behavior after CCI. Additionally, CCI induced gene expression of μ, κ, and δ opioid receptors in the contralateral cortex and thalamus of IL-4 ko mice, paralleled by fast onset of morphine analgesia, but not in wt mice. We conclude that a lack of IL-4 leads to mechanical sensitivity; the compensatory hyperexpression of analgesic cytokines and opioid receptors after CCI, in turn, protects IL-4 ko mice from enhanced pain behavior after nerve lesion. KW - mouse models KW - animal behavior KW - sciatic nerves KW - spinal cord KW - opioids KW - cytokines KW - gene expression KW - mice Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137924 VL - 6 IS - 12 ER - TY - JOUR A1 - Ruck, Tobias A1 - Bittner, Stefan A1 - Afzali, Ali Maisam A1 - Göbel, Kerstin A1 - Glumm, Sarah A1 - Kraft, Peter A1 - Sommer, Claudia A1 - Kleinschnitz, Christoph A1 - Preusse, Corinna A1 - Stenzel, Werner A1 - Wiendl, Heinz A1 - Meuth, Sven G. T1 - The NKG2D-IL-15 signaling pathway contributes to T-cell mediated pathology in inflammatory myopathies JF - Oncotarget N2 - NKG2D is an activating receptor on T cells, which has been implicated in the pathogenesis of autoimmune diseases. T cells are critically involved in idiopathic inflammatory myopathies (IIM) and have been proposed as specific therapeutic targets. However, the mechanisms underlying T cell-mediated progressive muscle destruction in IIM remain to be elucidated. We here determined the involvement of the NKG2D - IL-15 signaling pathway. Primary human myoblasts expressed NKG2D ligands, which were further upregulated upon inflammatory stimuli. In parallel, shedding of the soluble NKG2D ligand MICA (sMICA) decreased upon inflammation potentially diminishing inhibition of NKG2D signaling. Membrane-related expression of IL-15 by myoblasts induced differentiation of naive CD8\(^+\) T cells into highly activated, cytotoxic \(CD8^+NKG2D^{high}\) T cells demonstrating NKG2D-dependent lysis of myoblasts in vitro. \(CD8^+NKG2D^{high}\) T cell frequencies were increased in the peripheral blood of polymyositis (PM) patients and correlated with serum creatinine kinase concentrations, while serum sMICA levels were not significantly changed. In muscle biopsy specimens from PM patients expression of the NKG2D ligand MICA/B was upregulated, IL-15 was expressed by muscle cells, CD68\(^+\) macrophages as well as CD4\(^+\) T cells, and \(CD8^+NKG2D^+\) cells were frequently detected within inflammatory infiltrates arguing for a local signaling circuit in the inflammatory muscle milieu. In conclusion, the NKG2D - IL-15 signaling pathway contributes to progressive muscle destruction in IIM potentially opening new therapeutic avenues. KW - MIC ligands KW - pathology section KW - T cell activation KW - idiopathic inflammatory myopathies KW - polymyositis KW - IL-15 KW - NKG2D KW - receptor KW - expression KW - lymphokine-activated killer KW - human muscle-cells KW - multiple sclerosis KW - celiac disease KW - tumor immunity KW - NKG2D ligands KW - cutting edge Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136047 VL - 6 IS - 41 ER - TY - JOUR A1 - Burlina, Alessandro P. A1 - Sims, Katherine B. A1 - Politei, Juan M. A1 - Bennett, Gary J. A1 - Baron, Ralf A1 - Sommer, Claudia A1 - Moller, Anette Torvin A1 - Hilz, Max J. T1 - Early diagnosis of peripheral nervous system involvement in Fabry disease and treatment of neuropathic pain: the report of an expert panel JF - BMC Neurology N2 - Background: Fabry disease is an inherited metabolic disorder characterized by progressive lysosomal accumulation of lipids in a variety of cell types, including neural cells. Small, unmyelinated nerve fibers are particularly affected and small fiber peripheral neuropathy often clinically manifests at young age. Peripheral pain can be chronic and/or occur as provoked attacks of excruciating pain. Manifestations of dysfunction of small autonomic fibers may include, among others, impaired sweating, gastrointestinal dysmotility, and abnormal pain perception. Patients with Fabry disease often remain undiagnosed until severe complications involving the kidney, heart, peripheral nerves and/or brain have arisen. Methods: An international expert panel convened with the goal to provide guidance to clinicians who may encounter unrecognized patients with Fabry disease on how to diagnose these patients early using simple diagnostic tests. A further aim was to offer recommendations to control neuropathic pain. Results: We describe the neuropathy in Fabry disease, focusing on peripheral small fiber dysfunction - the hallmark of early neurologic involvement in this disorder. The clinical course of peripheral pain is summarized, and the importance of medical history-taking, including family history, is highlighted. A thorough physical examination (e. g., angiokeratoma, corneal opacities) and simple non-invasive sensory perception tests could provide clues to the diagnosis of Fabry disease. Reported early clinical benefits of enzyme replacement therapy include reduction of neuropathic pain, and adequate management of residual pain to a tolerable and functional level can substantially improve the quality of life for patients. Conclusions: Our recommendations can assist in diagnosing Fabry small fiber neuropathy early, and offer clinicians guidance in controlling peripheral pain. This is particularly important since management of pain in young patients with Fabry disease appears to be inadequate. KW - Enzyme replacement therapy KW - Quality of life KW - Small-fiber neuropathy KW - Rochester diabetic neuropathy KW - Randomized controlled trial KW - Agalsidase beta therapy KW - Outcome survey KW - Pharmacological management KW - Clinical manifestations KW - Alpha galactosidase KW - Diagnosis KW - Fabry KW - Disease KW - Neuropathy KW - Pain KW - Treatment Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-135309 VL - 11 IS - 61 ER - TY - JOUR A1 - Cruccu, Giorgio A1 - Pennisi, Elena M. A1 - Antonini, Giovanni A1 - Biasiotta, Antonella A1 - Di Stefano, Giulia A1 - La Cesa, Silvia A1 - Leone, Caterina A1 - Raffa, Salvatore A1 - Sommer, Claudia A1 - Truini, Andrea T1 - Trigeminal isolated sensory neuropathy (TISN) and FOSMN syndrome: despite a dissimilar disease course do they share common pathophysiological mechanisms? JF - BMC Neurology N2 - Background: Patients presenting with bilateral trigeminal hypoesthesia may go on to have trigeminal isolated sensory neuropathy, a benign, purely trigeminal neuropathy, or facial-onset sensory motor neuronopathy (FOSMN), a malignant life-threatening condition. No diagnostic criteria can yet differentiate the two conditions at their onset. Nor is it clear whether the two diseases are distinct entities or share common pathophysiological mechanisms. Methods: Seeking pathophysiological and diagnostic information to distinguish these two conditions at their onset, in this neurophysiological and morphometric study we neurophysiologically assessed function in myelinated and unmyelinated fibres and histologically examined supraorbital nerve biopsy specimens with optic and electron microscopy in 13 consecutive patients with recent onset trigeminal hypoesthesia and pain. Results: The disease course distinctly differed in the 13 patients. During a mean 10 year follow-up whereas in eight patients the disease remained relatively stable, in the other five it progressed to possibly life-threatening motor disturbances and extra-trigeminal spread. From two to six years elapsed between the first sensory symptoms and the onset of motor disorders. In patients with trigeminal isolated sensory neuropathy (TISN) and in those with FOSMN neurophysiological and histological examination documented a neuronopathy manifesting with trigeminal nerve damage selectively affecting myelinated fibres, but sparing the Ia-fibre-mediated proprioceptive reflex. Conclusions: Although no clinical diagnostic criteria can distinguish the two conditions at onset, neurophysiological and nerve-biopsy findings specify that in both disorders trigeminal nerve damage manifests as a dissociated neuronopathy affecting myelinated and sparing unmyelinated fibres, thus suggesting similar pathophysiological mechanisms. KW - amyotrophic-lateral-sclerosis KW - atrophy Kennedys-disease KW - trigeminal nerve KW - neuronopathy KW - trigeminal neuropathy KW - FOSMN KW - facial pain KW - Sjorgens-syndrome KW - reflex KW - afferents KW - neuralgia KW - pathways KW - humans KW - fibers Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-114249 SN - 1471-2377 VL - 14 ER - TY - JOUR A1 - Bischoff, Joakim M. A1 - Ringsted, Thomas K. A1 - Petersen, Marian A1 - Sommer, Claudia A1 - Üçeyler, Nurcan A1 - Werner, Mads U. T1 - A Capsaicin (8%) Patch in the Treatment of Severe Persistent Inguinal Postherniorrhaphy Pain: A Randomized, Double-Blind, Placebo-Controlled Trial JF - PLOS ONE N2 - Background: Persistent pain after inguinal herniorrhaphy is a disabling condition with a lack of evidence-based pharmacological treatment options. This randomized placebo-controlled trial investigated the efficacy of a capsaicin 8% cutaneous patch in the treatment of severe persistent inguinal postherniorrhaphy pain. Methods: Forty-six patients with persistent inguinal postherniorrhaphy pain were randomized to receive either a capsaicin 8% patch or a placebo patch. Pain intensity (Numerical Rating Scale [NRS 0-10]) was evaluated under standardized conditions (at rest, during movement, and during pressure) at baseline and at 1, 2 and 3 months after patch application. Skin punch biopsies for intraepidermal nerve fiber density (IENFD) measurements were taken at baseline and 1 month after patch application. Quantitative sensory testing was performed at baseline and at 1, 2, and 3 months after patch application. The primary outcome was comparisons of summed pain intensity differences (SPIDs) between capsaicin and placebo treatments at 1, 2 and 3 months after patch application (significance level P<0.01). Results: The maximum difference in SPID, between capsaicin and placebo treatments, was observed at 1 month after patch application, but the pain reduction was not significant (NRS, mean difference [95% CI]: 5.0 [0.09 to 9.9]; P=0.046). No differences in SPID between treatments were observed at 2 and 3 months after patch application. Changes in IENFD on the pain side, from baseline to 1 month after patch application, did not differ between capsaicin and placebo treatment: 1.9 [-0.1 to 3.9] and 0.6 [-1.2 to 2.5] fibers/mm, respectively (P=0.32). No significant changes in sensory function, sleep quality or psychological factors were associated with capsaicin patch treatment. Conclusions: The study did not demonstrate significant differences in pain relief between capsaicin and placebo treatment, although a trend toward pain improvement in capsaicin treated patients was observed 1 month after patch application. KW - postherpetic neuralgia KW - long-term pain KW - crossover trial KW - neuropathic pain KW - risk factors KW - cutaneous patch KW - scale KW - hernia repair KW - interference KW - validation Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115198 SN - 1932-6203 VL - 9 IS - 10 ER - TY - JOUR A1 - Üçeyler, Nurcan A1 - Valet, Michael A1 - Kafke, Waldemar A1 - Tölle, Thomas R. A1 - Sommer, Claudia T1 - Local and Systemic Cytokine Expression in Patients with Postherpetic Neuralgia N2 - Background Postherpetic neuralgia (PHN) is the painful complication of a varicella zoster virus reactivation. We investigated the systemic and local gene expression of pro- and anti-inflammatory cytokine expression in patients with PHN. Methods Thirteen patients with PHN at the torso (Th4-S1) were recruited. Skin punch biopsies were obtained from the painful and the contralateral painless body area for intraepidermal nerve fiber density (IENFD) and cytokine profiling. Additionally, blood was withdrawn for systemic cytokine expression and compared to blood values of healthy controls. We analyzed the gene expression of selected pro- and anti-inflammatory cytokines (tumor necrosis factor-alpha [TNF] and interleukins [IL]-1β, IL-2, and IL-8). Results IENFD was lower in affected skin compared to unaffected skin (p<0.05), while local gene expression of pro- and anti-inflammatory cytokines did not differ except for two patients who had 7fold higher IL-6 and 10fold higher IL-10 gene expression in the affected skin compared to the contralateral unaffected skin sample. Also, the systemic expression of cytokines in patients with PHN and in healthy controls was similar. Conclusion While the systemic and local expression of the investigated pro- and anti-inflammatory cytokines was not different from controls, this may have been influenced by study limitations like the low number of patients and different disease durations. Furthermore, other cytokines or pain mediators need to be considered. KW - neuropathic pain KW - cytokines KW - pain sensation KW - gene expression KW - nerve fibres KW - RNA extraction KW - shingles KW - skin tumors Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-113041 ER - TY - JOUR A1 - Üçeyler, Nurcan A1 - Kahn, Ann-Kathrin A1 - Kramer, Daniela A1 - Zeller, Daniel A1 - Casanova-Molla, Jordi A1 - Wanner, Christoph A1 - Weidemann, Frank A1 - Katsarava, Zaza A1 - Sommer, Claudia T1 - Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case–control study JF - BMC Neurology N2 - Background Fabry disease is an inborn lysosomal storage disorder which is associated with small fiber neuropathy. We set out to investigate small fiber conduction in Fabry patients using pain-related evoked potentials (PREP). Methods In this case–control study we prospectively studied 76 consecutive Fabry patients for electrical small fiber conduction in correlation with small fiber function and morphology. Data were compared with healthy controls using non-parametric statistical tests. All patients underwent neurological examination and were investigated with pain and depression questionnaires. Small fiber function (quantitative sensory testing, QST), morphology (skin punch biopsy), and electrical conduction (PREP) were assessed and correlated. Patients were stratified for gender and disease severity as reflected by renal function. Results All Fabry patients (31 men, 45 women) had small fiber neuropathy. Men with Fabry disease showed impaired cold (p < 0.01) and warm perception (p < 0.05), while women did not differ from controls. Intraepidermal nerve fiber density (IENFD) was reduced at the lower leg (p < 0.001) and the back (p < 0.05) mainly of men with impaired renal function. When investigating A-delta fiber conduction with PREP, men but not women with Fabry disease had lower amplitudes upon stimulation at face (p < 0.01), hands (p < 0.05), and feet (p < 0.01) compared to controls. PREP amplitudes further decreased with advance in disease severity. PREP amplitudes and warm (p < 0.05) and cold detection thresholds (p < 0.01) at the feet correlated positively in male patients. Conclusion Small fiber conduction is impaired in men with Fabry disease and worsens with advanced disease severity. PREP are well-suited to measure A-delta fiber conduction. KW - Fabry disease KW - Pain-related evoked potentials KW - Small fiber neuropathy KW - A-delta fibers Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-96527 UR - http://www.biomedcentral.com/1471-2377/13/47 ER -