@phdthesis{Patzko2012, author = {Patzk{\´o}, {\´A}gnes}, title = {CSF-1 receptor as a target for the treatment of Charcot-Marie-Tooth disease 1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85325}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Previous studies by our group revealed that chronic low grade inflammation implicating phagocytosing macrophages is a highly relevant mechanism in the pathogenesis of Charcot-Marie-Tooth disease. The lack of CSF-1, the primary regulator of macrophage function and survival, led to a robust and persistent amelioration of the phenotype in two authentic mouse models of CMT. Moreover, a close contact between CSF-1 producing fibroblasts and endoneurial macrophages carrying CSF-1R has been confirmed in nerve biopsies of CMT patients, further supporting the clinical significance of this pathway. In the current study we treated 3 distinct mouse models of CMT1: the PMP22tg mice as a model for CMT1A, the P0+/- mice as a model for CMT1B and the Cx32def mice as a model for CMT1X, with a CSF-1R specific kinase (c-FMS) inhibitor (800-1200 mg PLX5622/ kg chow) according to different treatment regimes mimicking an ideal early onset treatment, a late onset treatment and the withdrawal of the drug. Using the above mentioned doses of PLX5622, we documented a dramatic decrease in macrophage numbers in the PNS of all 3 myelin mutants, except for the quadriceps nerve of Cx32def mice. Fibroblast numbers remained unchanged in treated animals. Surprisingly, in spite of the decrease in the number of detrimental macrophages we could not detect an unequivocal phenotypic improvement. CMAP amplitudes were reduced in both wild type and myelin mutant mice treated with CSF-1R inhibitor in comparison to untreated littermates. Corresponding to the electrophysiological findings, the axon number and the percentage of large diameter axons were reduced in the quadriceps nerve of treated P0+/- and Cx32def mice. By contrast we observed a higher number of fully myelinated axons, in parallel with a decrease in the percentage of demyelinated (and hypermyelinated in PMP22tg mice) fibers in the ventral roots of P0+/- mice treated with CSF-1R inhibitor from 3 months up to 6 months of age and PMP22tg animals treated from 9 months up to 15 months of age. Our results indicate that CSF-1R inhibitor has the potential to improve the demyelinating phenotype of at least two models of CMT1. Nevertheless, further studies are necessary (for example with lower doses of the inhibitor) to minimize or even eliminate the putative neurotoxic effect we observed with high dose treatment conditions.}, subject = {Makrophage}, language = {en} } @phdthesis{Dreykluft2013, author = {Dreykluft, Angela}, title = {The PD-1/B7-H1 Pathway in a Transgenic Mouse Model for Spontaneous Autoimmune Neuroinflammation: Immunological Studies on Devic B7-H1-/- Mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-83288}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Multiple sclerosis is an autoimmune disease of the central nervous system characterized by inflammatory, demyelinating lesions and neuronal death. Formerly regarded as a variant of MS, neuromyelitis optica (NMO)/Devic's disease is now recognized as a distinct neurological disorder exhibiting characteristic inflammatory and demyelinated foci in the optic nerves and the spinal cord sparing the brain. With the introduction of the double-transgenic "Devic mouse" model featuring spontaneous, adjuvant-free incidence of autoimmune neuroinflammation due to the interaction of transgenic MOG-specific T and B cells, a promising tool was found for the analysis of factors triggering or preventing autoimmunity. The co-inhibitory molecule B7-H1 has been proposed to contribute to the maintenance of peripheral tolerance and to confine autoimmune inflammatory damage via the PD-1/B7-H1 pathway. Compared to Devic B7-H1+/+ mice, Devic B7-H1-/- mice developed clinical symptoms with a remarkably higher incidence rate and faster kinetics emphasized by deteriorated disease courses and a nearly quadrupled mortality rate. Remarkably enlarged immune-cell accumulation in the CNS of Devic B7-H1-/- mice, in particular of activated MOG-specific CD4+ T cells, correlated with the more severe clinical features. Our studies showed that the CNS not only was the major site of myelin-specific CD4+ T-cell activation but also that B7-H1 expression within the target organ significantly influenced T-cell activation and differentiation levels. Analysis at disease maximum revealed augmented accumulation of MOG-specific CD4+ T cells in the peripheral lymphoid organs of Devic B7-H1-/- mice partly due to increased T-cell proliferation rates. Transgenic MOG-specific B cells of Devic B7-H1-/- mice activated MOG-specific CD4+ T cells more efficiently than B cells of Devic B7-H1+/+ mice. This observation indicated a relevant immune-modulating role of B7-H1 on APCs (antigen-presenting cells) in this mouse model. We also assumed altered thymic selection processes to be involved in increased peripheral CD4+ T-cell numbers of Devic B7-H1-/- mice as we found more thymocytes expressing the transgenic MOG-specific T-cell receptor (TCR). Moreover, preliminary in vitro experiments hinted on an enhanced survival of TCRMOG-transgenic CD4+ T cells of Devic B7-H1-/- mice; a mechanism that might as well have led to higher peripheral T-cell accumulation. Elevated levels of MOG-specific CD4+ T cells in the periphery of Devic B7-H1-/- mice could have entailed the higher quantities in the CNS. However, mechanisms such as CNS-specific proliferation and/or apoptosis/survival could also have contributed. This should be addressed in future investigations. Judging from in vitro migration assays and adoptive transfer experiments on RAG-1-/- recipient mice, migratory behavior of MOG-specific CD4+ T cells of Devic B7-H1+/+ and Devic B7-H1-/- mice seemed not to differ. However, enhanced expression of the transmigration-relevant integrin LFA-1 on CD4+ T cells in young symptom-free Devic B7-H1-/- mice might hint on temporally differently pronounced transmigration capacities during the disease course. Moreover, we attributed the earlier conversion of CD4+ T cells into Th1 effector cells in Devic B7-H1-/- mice during the initiation phase to the lack of co-inhibitory signaling via PD-1/B7-H1 possibly leading to an accelerated disease onset. Full blown autoimmune inflammatory processes could have masked these slight effects of B7-H1 in the clinical phase. Accordingly, at peak of the disease, Th1 and Th17 effector functions of peripheral CD4+ T cells were comparable in both mouse groups. Moreover, judging from titers of MOG-specific IgG1 and IgM antibodies, alterations in humoral immunity were not detected. Therefore, clinical differences could not be explained by altered T-cell or B-cell effector functions at disease maximum. B7-H1 rather seemed to take inhibitory effect in the periphery during the initiation phase only and consistently within the target organ by parenchymal expression. Our observations indicate that B7-H1 plays a relevant role in the regulation of T-cell responses in this mouse model for spontaneous CNS autoimmunity. By exerting immune-modulating effects in the preclinical as well as the clinical phase of the disease, B7-H1 contributed to the confinement of the immunopathological tissue damage in Devic B7-H1+/+ mice mirrored by later disease onsets and lower disease scores. As a model for spontaneous autoimmunity featuring a close to 100 \% incidence rate, the Devic B7-H1-/- mouse may prove instrumental in clarifying disease-triggering and -limiting factors and in validating novel therapeutic approaches in the field of autoimmune neuroinflammation, in particular the human Devic's disease.}, subject = {Autoimmunit{\"a}t}, language = {en} } @phdthesis{Groh2013, author = {Groh, Janos Michael}, title = {Pathogenic impact of immune cells in mouse models of neuronal ceroid lipofuscinosis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-77684}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {The neuronal ceroid lipofuscinoses (NCLs) are fatal neurodegenerative disorders in which the visual system is affected in early stages of disease. A typical accompanying feature is neuroinflammation, the pathogenic impact of which is presently unknown. In this study, the role of inflammatory cells in the pathogenesis was investigated in Palmitoyl-protein thioesterase 1-deficient (Ppt1-/-) and Ceroidlipofuscinosis, neuronal 3-deficient (Cln3-/-) mice, models of the infantile and juvenile forms of NCL, respectively. Focusing predominantly on the visual system, an infiltration of CD8+ cytotoxic Tlymphocytes and an activation of microglia/macrophage-like cells was observed early in disease. To analyze the pathogenic impact of lymphocytes, Ppt1-/- mice were crossbred with mice lacking lymphocytes (Rag1-/-) and axonal transport, perturbation and neuronal survival were scored. Lack of lymphocytes led to a significant amelioration of neuronal disease and reconstitution experiments revealed a crucial role of CD8+ cytotoxic T-lymphocytes. Lack of lymphocytes also caused an improved clinical phenotype and extended longevity. To investigate the impact of microglia/macrophage-like cells, Ppt1-/- and Cln3-/- mice were crossbred with mice lacking sialoadhesin (Sn-/-), a monocyte lineage-restricted cell adhesion molecule important for interactions between macrophage-like cells and lymphocytes. Similar to the lack of lymphocytes, absence of sialoadhesin significantly ameliorated the disease in Ppt1-/- and Cln3-/- mice. Taken together, both T-lymphocytes and microglia/macrophage-like cells were identified as pathogenic mediators in two distinct forms of fatal inherited neurodegenerative storage disorders. These studies expand the concept of secondary inflammation as a common pathomechanistic feature in some neurological diseases and provide novel insights that may be crucial for developing treatment strategies for different forms of NCL.}, subject = {Nervendegeneration}, language = {en} } @techreport{LinkerMeuthMagnusetal.2012, author = {Linker, Ralf, A. and Meuth, Sven G. and Magnus, Tim and Korn, Thomas and Kleinschnitz, Christoph}, title = {Report on the 4'th scientific meeting of the "Verein zur F{\"o}rderung des Wissenschaftlichen Nachwuchses in der Neurologie" (NEUROWIND e.V.) held in Motzen, Germany, Nov. 2'nd - Nov. 4'th, 2012 [meeting report]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76407}, year = {2012}, abstract = {From November 2nd - 4th 2012, the 4th NEUROWIND e.V. meeting was held in Motzen, Brandenburg, Germany. Again more than 60 participants, predominantly at the doctoral student or postdoc level, gathered to share their latest findings in the fields of neurovascular research, neurodegeneration and neuroinflammation. Like in the previous years, the symposium provided an excellent platform for scientific exchange and the presentation of innovative projects in the stimulating surroundings of the Brandenburg outback. This year's keynote lecture on the pathophysiological relevance of neuronal networks was given by Christian Gerloff, Head of the Department of Neurology at the University Clinic of Hamburg-Eppendorf. Another highlight of the meeting was the awarding of the NEUROWIND e.V. prize for young scientists working in the field of experimental neurology. The award is donated by the Merck Serono GmbH, Darmstadt, Germany and is endowed with 20.000 Euro. This year the jury decided unanimously to adjudge the award to Michael Gliem from the Department of Neurology at the University Clinic of D{\"u}sseldorf (group of Sebastian Jander), Germany, for his outstanding work on different macrophage subsets in the pathogenesis of ischemic stroke published in the Annals of Neurology in 2012.}, subject = {Medizin}, language = {en} } @article{ZellerDangWeiseetal.2012, author = {Zeller, Daniel and Dang, Su-Yin and Weise, David and Rieckmann, Peter and Toyka, Klaus V. and Classen, Joseph}, title = {Excitability decreasing central motor plasticity is retained in multiple sclerosis patients}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76333}, year = {2012}, abstract = {Background: Compensation of brain injury in multiple sclerosis (MS) may in part work through mechanisms involving neuronal plasticity on local and interregional scales. Mechanisms limiting excessive neuronal activity may have special significance for retention and (re-)acquisition of lost motor skills in brain injury. However, previous neurophysiological studies of plasticity in MS have investigated only excitability enhancing plasticity and results from neuroimaging are ambiguous. Thus, the aim of this study was to probe long-term depression-like central motor plasticity utilizing continuous theta-burst stimulation (cTBS), a non-invasive brain stimulation protocol. Because cTBS also may trigger behavioral effects through local interference with neuronal circuits, this approach also permitted investigating the functional role of the primary motor cortex (M1) in force control in patients with MS. Methods: We used cTBS and force recordings to examine long-term depression-like central motor plasticity and behavioral consequences of a M1 lesion in 14 patients with stable mild-to-moderate MS (median EDSS 1.5, range 0 to 3.5) and 14 age-matched healthy controls. cTBS consisted of bursts (50 Hz) of three subthreshold biphasic magnetic stimuli repeated at 5 Hz for 40 s over the hand area of the left M1. Corticospinal excitability was probed via motor-evoked potentials (MEP) in the abductor pollicis brevis muscle over M1 before and after cTBS. Force production performance was assessed in an isometric right thumb abduction task by recording the number of hits into a predefined force window. Results: cTBS reduced MEP amplitudes in the contralateral abductor pollicis brevis muscle to a comparable extent in control subjects (69 ± 22\% of baseline amplitude, p < 0.001) and in MS patients (69 ± 18\%, p < 0.001). In contrast, postcTBS force production performance was only impaired in controls (2.2 ± 2.8, p = 0.011), but not in MS patients (2.0 ± 4.4, p = 0.108). The decline in force production performance following cTBS correlated with corticomuscular latencies (CML) in MS patients, but did not correlate with MEP amplitude reduction in patients or controls. Conclusions: Long-term depression-like plasticity remains largely intact in mild-to-moderate MS. Increasing brain injury may render the neuronal networks less responsive toward lesion-induction by cTBS.}, subject = {Medizin}, language = {en} } @article{KunzePhamRaslanetal.2012, author = {Kunze, Ekkehard and Pham, Mirko and Raslan, Furat and Stetter, Christian and Lee, Jin-Yul and Solymosi, Laszlo and Ernestus, Ralf-Ingo and Hamilton Vince, Giles and Westermaier, Thomas}, title = {Value of Perfusion CT, Transcranial Doppler Sonography and Neurological Examination to detect delayed Vasospasm after aneurysmal Subarachnoid Hemorrhage [Research Article]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76241}, year = {2012}, abstract = {Background If detected in time, delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) may be treated by balloon angioplasty or chemical vasospasmolysis in order to enhance cerebral blood flow (CBF) and protect the brain from ischemic damage. This study was conceived to compare the diagnostic accuracy of detailed neurological examination, Transcranial Doppler Sonography (TCD), and Perfusion-CT (PCT) to detect angiographic vasospasm. Methods The sensitivity, specificity, positive and negative predictive values of delayed ischemic neurological deterioration (DIND), pathological findings on PCT- maps, and accelerations of the mean flow velocity (MVF) were calculated. Results The accuracy of DIND to predict angiographic vasospasm was 0.88. An acceleration of MFV in TCD (>140 cm/s) had an accuracy of 0.64, positive PCT-findings of 0.69 with a higher sensitivity, and negative predictive value than TCD. Interpretation Neurological assessment at close intervals is the most sensitive and specific parameter for cerebral vasospasm. PCT has a higher accuracy, sensitivity and negative predictive value than TCD. If detailed neurological evaluation is possible, it should be the leading parameter in the management and treatment decisions. If patients are not amenable to detailed neurological examination, PCT at regular intervals is a helpful tool to diagnose secondary vasospasm after aneurysmal SAH.}, subject = {Medizin}, language = {en} } @article{RaslanAlbertWeissenbergerWestermaieretal.2012, author = {Raslan, Furat and Albert-Weißenberger, Christiane and Westermaier, Thomas and Saker, Saker and Kleinschmitz, Christoph and Lee, Jin-Yul}, title = {A modified double injection model of cisterna magna for the study of delayed cerebral vasospasm following subarachnoid hemorrhage in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76038}, year = {2012}, abstract = {Delayed cerebral vasospasm following subarachnoid hemorrhage (SAH) is a serious medical complication, characterized by constriction of cerebral arteries leading to varying degrees of cerebral ischemia. Numerous clinical and experimental studies have been performed in the last decades; however, the pathophysiologic mechanism of cerebral vasospasm after SAH still remains unclear. Among a variety of experimental SAH models, the double hemorrhage rat model involving direct injection of autologous arterial blood into the cisterna magna has been used most frequently for the study of delayed cerebral vasospasm following SAH in last years. Despite the simplicity of the technique, the second blood injection into the cisterna magna may result in brainstem injury leading to high mortality. Therefore, a modified double hemorrhage model of cisterna magna has been developed in rat recently. We describe here step by step the surgical technique to induce double SAH and compare the degree of vasospasm with other cisterna magna rat models using histological assessment of the diameter and cross-sectional area of the basilar artery}, subject = {Medizin}, language = {en} } @article{WestermaierStetterRaslanetal.2012, author = {Westermaier, Thomas and Stetter, Christian and Raslan, Furat and Vinc, Giles Hamilton and Ernestus, Ralf-Ingo}, title = {Brain edema formation correlates with perfusion deficit during the first six hours after experimental subarachnoid hemorrhage in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75765}, year = {2012}, abstract = {Background: Severe brain edema is observed in a number of patients suffering from subarachnoid hemorrhage (SAH). Little is known about its pathogenesis and time-course in the first hours after SAH. This study was performed to investigate the development of brain edema and its correlation with brain perfusion after experimental SAH. Methods: Male Sprague-Dawley rats, randomly assigned to one of six groups (n = 8), were subjected to SAH using the endovascular filament model or underwent a sham operation. Animals were sacrificed 15, 30, 60, 180 or 360 minutes after SAH. Intracranial pressure (ICP), mean arterial blood pressure (MABP), cerebral perfusion pressure (CPP) and bilateral local cerebral blood flow (LCBF) were continuously measured. Brain water content (BWC) was determined by the wet/dry-weight method. Results: After SAH, CPP and LCBF rapidly decreased. The decline of LCBF markedly exceeded the decline of CPP and persisted until the end of the observation period. BWC continuously increased. A significant correlation was observed between the BWC and the extent of the perfusion deficit in animals sacrificed after 180 and 360 minutes. Conclusions: The significant correlation with the perfusion deficit after SAH suggests that the development of brain edema is related to the extent of ischemia and acute vasoconstriction in the first hours after SAH.}, subject = {Medizin}, language = {en} } @article{KleinschnitzMeuthMagnusetal.2012, author = {Kleinschnitz, Christph and Meuth, Sven G. and Magnus, Tim and Korn, Thomas and Linker, Ralf A.}, title = {Report on the 3'rd scientific meeting of the "Verein zur F{\"o}rderung des Wissenschaftlichen Nachwuchses in der Neurologie" (NEUROWIND e.V.) held in Motzen, Germany, Nov. 4'th - Nov. 6'th, 2011}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75388}, year = {2012}, abstract = {From November 4th- 6th 2011, the 3rd NEUROWIND e.V. meeting was held in Motzen, Brandenburg, Germany. Like in the previous years, the meeting provided an excellent platform for scientific exchange and the presentation of innovative projects for young colleagues in the fields of neurovascular research, neuroinflammation and neurodegeneration. As kick-off to the scientific sessions, Reinhard Hohlfeld, Head of the Institute for Clinical Neuroimmunology in Munich, gave an illustrious overview on the many fascinations of neuroimmunologic research. A particular highlight on the second day of the meeting was the award of the 1'st NEUROWIND e.V. prize for young academics in the field of experimental neurology. This award is posted for young colleagues under the age of 35 with a significant achievement in the field of neurovascular research, neuroinflammation or neurodegeneration and comprises an amount of 20.000 Euro, founded by Merck Serono GmbH, Darmstadt. Germany. The first prize was awarded to Ivana Nikic from Martin Kerschensteiner's group in Munich for her brilliant work on a reversible form of axon damage in experimental autoimmune encephalomyelitis and multiple sclerosis, published in Nature Medicine in 2011. This first prize award ceremony was a great incentive for the next call for proposals now upcoming in 2012.}, subject = {Medizin}, language = {en} } @article{AlbertWeissenbergerVarrallyayRaslanetal.2012, author = {Albert-Weißenberger, Christiane and V{\´a}rrallyay, Csan{\´a}d and Raslan, Furat and Kleinschnitz, Christoph and Sir{\´e}n, Anna-Leena}, title = {An experimental protocol for mimicking pathomechanisms of traumatic brain injury in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75368}, year = {2012}, abstract = {Traumatic brain injury (TBI) is a result of an outside force causing immediate mechanical disruption of brain tissue and delayed pathogenic events. In order to examine injury processes associated with TBI, a number of rodent models to induce brain trauma have been described. However, none of these models covers the entire spectrum of events that might occur in TBI. Here we provide a thorough methodological description of a straightforward closed head weight drop mouse model to assess brain injuries close to the clinical conditions of human TBI.}, subject = {Medizin}, language = {en} } @article{GeisWeishauptGruenewaldetal.2011, author = {Geis, Christian and Weishaupt, Andreas and Gr{\"u}newald, Benedikt and Wultsch, Thomas and Reif, Andreas and Gerlach, Manfred and Dirkx, Ron and Solimena, Michele and Perani, Daniela and Heckmann, Manfred and Toyka, Klaus V. and Folli, Franco and Sommer, Claudia}, title = {Human Stiff-Person Syndrome IgG Induces Anxious Behavior in Rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-74757}, year = {2011}, abstract = {Background: Anxiety is a heterogeneous behavioral domain playing a role in a variety of neuropsychiatric diseases. While anxiety is the cardinal symptom in disorders such as panic disorder, co-morbid anxious behavior can occur in a variety of diseases. Stiff person syndrome (SPS) is a CNS disorder characterized by increased muscle tone and prominent agoraphobia and anxiety. Most patients have high-titer antibodies against glutamate decarboxylase (GAD) 65. The pathogenic role of these autoantibodies is unclear. Methodology/Principal Findings: We re-investigated a 53 year old woman with SPS and profound anxiety for GABA-A receptor binding in the amygdala with (11)C-flumazenil PET scan and studied the potential pathogenic role of purified IgG from her plasma filtrates containing high-titer antibodies against GAD 65. We passively transferred the IgG fraction intrathecally into rats and analyzed the effects using behavioral and in vivo electrophysiological methods. In cell culture, we measured the effect of patient IgG on GABA release from hippocampal neurons. Repetitive intrathecal application of purified patient IgG in rats resulted in an anxious phenotype resembling the core symptoms of the patient. Patient IgG selectively bound to rat amygdala, hippocampus, and frontal cortical areas. In cultured rat hippocampal neurons, patient IgG inhibited GABA release. In line with these experimental results, the GABA-A receptor binding potential was reduced in the patient's amygdala/hippocampus complex. No motor abnormalities were found in recipient rats. Conclusion/Significance: The observations in rats after passive transfer lead us to propose that anxiety-like behavior can be induced in rats by passive transfer of IgG from a SPS patient positive for anti-GAD 65 antibodies. Anxiety, in this case, thus may be an antibody-mediated phenomenon with consecutive disturbance of GABAergic signaling in the amygdala region.}, subject = {Medizin}, language = {en} } @article{ChenPalmLeschetal.2011, author = {Chen, Y. and Palm, F. and Lesch, K. P. and Gerlach, M. and Moessner, R. and Sommer, C.}, title = {5-hydroxyindolacetic acid (5-HIAA), a main metabolite of serotonin, is responsible for complete Freund's adjuvant-induced thermal hyperalgesia in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68858}, year = {2011}, abstract = {Background: The role of serotonin (5-hydroxytrptamine, 5-HT) in the modulation of pain has been widely studied. Previous work led to the hypothesis that 5-hydroxyindolacetic acid (5-HIAA), a main metabolite of serotonin, might by itself influence pain thresholds. Results: In the present study, we investigated the role of 5-HIAA in inflammatory pain induced by intraplantar injection of complete Freund's adjuvant (CFA) into the hind paw of mice. Wild-type mice were compared to mice deficient of the 5-HT transporter (5-HTT-/- mice) using behavioral tests for hyperalgesia and high-performance liquid chromatography (HPLC) to determine tissue levels of 5-HIAA. Wild-type mice reproducibly developed thermal hyperalgesia and paw edema for 5 days after CFA injection. 5-HTT-/- mice treated with CFA had reduced thermal hyperalgesia on day 1 after CFA injection and normal responses to heat hereafter. The 5-HIAA levels in spinal cord and sciatic nerve as measured with HPLC were lower in 5-HTT-/- mice than in wild-type mice after CFA injection. Pretreatment of wild-type mice with intraperitoneal injection of para-chlorophenylalanine (p-CPA), a serotonin synthesis inhibitor, resulted in depletion of the 5-HIAA content in spinal cord and sciatic nerve and decrease in thermal hyperalgesia in CFA injected mice. The application of exogenous 5-HIAA resulted in potentiation of thermal hyperalgesia induced by CFA in 5-HTT-/- mice and in wild-type mice pretreated with p- CPA, but not in wild-type mice without p-CPA pretreatment. Further, methysergide, a broad-spectrum serotonin receptor antagonist, had no effect on 5-HIAA-induced potentiation of thermal hyperalgesia in CFA-treated wildtype mice. Conclusion: Taken together, the present results suggest that 5-HIAA plays an important role in modulating peripheral thermal hyperalgesia in CFA induced inflammation, probably via a non-serotonin receptor mechanism.}, subject = {Medizin}, language = {en} } @phdthesis{Dang2011, author = {Dang, Su-Yin Judith}, title = {Funktionelle Bedeutung der Neuroplastizit{\"a}t bei Multipler Sklerose}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73817}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Die Multiple Sklerose ist eine chronische neurologische Erkrankung, welche in der industrialisierten Welt einen der h{\"a}ufigsten Gr{\"u}nde f{\"u}r eine bleibende Behinderung bei jungen Erwachsenen darstellt. Obwohl die ZNS-Sch{\"a}digung, charakterisiert durch Demyelinisierung und axonale Sch{\"a}digung im Rahmen entz{\"u}ndlicher Vorg{\"a}nge, durch verschiedene Reparaturmechanismen reduziert wird, akkumuliert die L{\"a}sionslast im zentralen Nervensystem mit der Zeit. T2-gewichtete MRT-Studien zeigen, dass die dargestellten Pathologien nur m{\"a}ßig mit den motorischen Defiziten korrelieren. Diese Diskrepanz wird unter anderem auf Vorg{\"a}nge der Neuroplastizit{\"a}t zur{\"u}ckgef{\"u}hrt, als deren Basismechanismen Langzeitpotenzierung (LTP) und -depression (LTD) gelten. In verschiedenen fMRT-Studien haben sich Hinweise ergeben, dass diese adaptiven Ver{\"a}nderungen zur Reorganisation kortikaler Repr{\"a}sentationmuster f{\"u}hren k{\"o}nnen, so dass bei MS-Patienten eine ausgedehntere Aktivierung ipsilateraler sensomotorischer Areale bei motorischen Aufgaben zu beobachten ist. Die transkranielle Magnetstimulation (TMS) bietet die M{\"o}glichkeit, mittels virtueller L{\"a}sionstechniken eine direkte Aussage {\"u}ber die kausale Beziehung zwischen Struktur und Funktion zu liefern. Die funktionelle Rolle ipsilateraler Motorareale wurde an 26 MS-Patienten, in Relation zu ihrer motorischen Beeintr{\"a}chtigung und ZNS-Sch{\"a}digung, und an nach Alter, Geschlecht und H{\"a}ndigkeit zugeordneten Kontrollprobanden, untersucht. Die motorische Leistungsf{\"a}higkeit wurde durch verschiedene Tests zur Handfunktion erhoben. Die ZNS-Sch{\"a}digung wurde mittels MR-Spektroskopie als NAA/Cr Quotient sowie durch die CML erhoben. Die Aufgabe zur einfachen Reaktionszeit (SRT) bestand aus einer isometrischen Abduktionsbewegung des rechten Daumens gegen einen Kraftaufnehmer auf ein akustisches Go-Signal. Mit TMS-Einzelreizen wurde mit Hilfe einer Neuronavigation eine reversible virtuelle L{\"a}sion {\"u}ber bestimmten Gehirnarealen, kontralateraler M1, ipsilateraler M1 und ipsilateraler PMd, erzeugt. Es wurde eine Kontrollstimulation {\"u}ber MO durchgef{\"u}hrt. Die TMS-Einzelreize wurden 100ms nach dem Go-Signal appliziert. Als SRT wurde der Zeitraum zwischen dem Go-Signal und EMG-Beginn im APB definiert. Die signifikanten SRT-Verl{\"a}ngerungen bei TMS {\"u}ber dem ipsilateralen M1 und dem ipsilateralen PMd zeigen, dass diese Regionen eine Rolle bei der motorischen Funktion bei MS spielen. Die fehlenden Korrelationen zwischen motorischen Funktionstest und NAA/Cr-Verh{\"a}ltnis sowie die inverse Korrelation zur kortikomuskul{\"a}ren Latenz sind durch strukturell von der krankheitsbedingten Pathologie betroffenen kompensierenden Gehirnregionen erkl{\"a}rbar. Bei dem Theta Burst Experiments (TBS) wurde ein virtueller L{\"a}sionseffekt durch eine repetitive TMS-Intervention {\"u}ber dem ipsilateralen M1 induziert. Die Ergebnisse zeigen {\"a}hnliche Ver{\"a}nderungen der Exzitabilit{\"a}t bei MS-Patienten und gesunden Kontrollprobanden, was schließen l{\"a}sst, dass die LTD bei mild bis moderat betroffenen MS-Patienten weitestgehend unbeeintr{\"a}chtigt ist. MS-Patienten zeigen im Vergleich zu den Kontrollen eine {\"a}hnliche Minderung der Verhaltensleistung, Trefferquote in ein Kraftfenster, der MS-Patienten im Kontrollvergleich. Die Ergebnisse zeigen, dass ipsilaterale motorische Areale in der Lage sind den prim{\"a}r motorischen Kortex soweit zu kompensieren, jedoch die F{\"a}higkeit zur Kompensation in fortgeschrittenen Krankheitsstadien eingeschr{\"a}nkt ist. Abschließend kann man zusammenfassen, dass die funktionelle Rekrutierung von ipsilateralen Motorarealen eine adaptive Antwort auf chronische Gehirnsch{\"a}digung bei MS-Patienten sein kann, allerdings mit Einschr{\"a}nkung der Kapazit{\"a}t in fortgeschrittenen Krankheitsstadien. Nachdem die synaptische Plastizit{\"a}t weitestgehend intakt scheint, sollte man besonders Mechanismen der sp{\"a}ten Phase der Plastizit{\"a}t f{\"o}rdern, welche auf eine langfristige kortikale Plastizit{\"a}t abzielen. Weitere Studien in diesem Forschungszweig k{\"o}nnten einen Beitrag zur Entwicklung therapeutischer Konzepte der Neurorehabilitation bei Multipler Sklerose leisten.}, subject = {Neuronale Plastizit{\"a}t}, language = {de} } @article{UeceylerBikoSommer2010, author = {Ueceyler, Nurcan and Biko, Lydia and Sommer, Claudia}, title = {MDL-28170 Has No Analgesic Effect on CCI Induced Neuropathic Pain in Mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68359}, year = {2010}, abstract = {The calpain inhibitor MDL-28710 blocks the early local pro-inflammatory cytokine gene expression in mice after chronic constriction nerve injury (CCI). Onehundred- thirteen wild type mice of C57Bl/6J background received CCI of the right sciatic nerve. Mechanical paw withdrawal thresholds and thermal withdrawal latencies were investigated at baseline and at 1, 3, and 7 days after CCI. Three application regimens were used for MDL-28170: a) single injection 40 min before CCI; b) serial injections of MDL- 28170 40 min before and up to day three after CCI; c) sustained application via intraperitoneal osmotic pumps. The control animals received the vehicle DMSO/PEG 400. The tolerable dose of MDL-28170 for mice was 30 mg/kg body weight, higher doses were lethal within the first hours after application. Mechanical withdrawal thresholds and thermal withdrawal latencies were reduced after CCI and did not normalize after single or serial injections, nor with application of MDL-28170 via osmotic pumps. Although the calpain inhibitor MDL-28170 inhibits the early local cytokine upregulation in the sciatic nerve after CCI, pain behavior is not altered. This finding implies that local cytokine upregulation after nerve injury alone is only one factor in the induction and maintenance of neuropathic pain.}, subject = {Medizin}, language = {en} } @article{ChenBoettgerReifetal.2010, author = {Chen, Yong and Boettger, Michael K. and Reif, Andreas and Schmitt, Angelika and Ueceyler, Nurcan and Sommer, Claudia}, title = {Nitric oxide synthase modulates CFA-induced thermal hyperalgesia through cytokine regulation in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68349}, year = {2010}, abstract = {Background: Although it has been largely demonstrated that nitric oxide synthase (NOS), a key enzyme for nitric oxide (NO) production, modulates inflammatory pain, the molecular mechanisms underlying these effects remain to be clarified. Here we asked whether cytokines, which have well-described roles in inflammatory pain, are downstream targets of NO in inflammatory pain and which of the isoforms of NOS are involved in this process. Results: Intraperitoneal (i.p.) pretreatment with 7-nitroindazole sodium salt (7-NINA, a selective neuronal NOS inhibitor), aminoguanidine hydrochloride (AG, a selective inducible NOS inhibitor), L-N(G)-nitroarginine methyl ester (L-NAME, a non-selective NOS inhibitor), but not L-N(5)-(1-iminoethyl)-ornithine (L-NIO, a selective endothelial NOS inhibitor), significantly attenuated thermal hyperalgesia induced by intraplantar (i.pl.) injection of complete Freund's adjuvant (CFA). Real-time reverse transcription-polymerase chain reaction (RT-PCR) revealed a significant increase of nNOS, iNOS, and eNOS gene expression, as well as tumor necrosis factor-alpha (TNF), interleukin-1 beta (IL-1b), and interleukin-10 (IL-10) gene expression in plantar skin, following CFA. Pretreatment with the NOS inhibitors prevented the CFA-induced increase of the pro-inflammatory cytokines TNF and IL-1b. The increase of the antiinflammatory cytokine IL-10 was augmented in mice pretreated with 7-NINA or L-NAME, but reduced in mice receiving AG or L-NIO. NNOS-, iNOS- or eNOS-knockout (KO) mice had lower gene expression of TNF, IL-1b, and IL-10 following CFA, overall corroborating the inhibitor data. Conclusion: These findings lead us to propose that inhibition of NOS modulates inflammatory thermal hyperalgesia by regulating cytokine expression.}, subject = {Medizin}, language = {en} } @article{BraeuningerKleinschnitzStoll2010, author = {Braeuninger, Stefan and Kleinschnitz, C. and Stoll, G.}, title = {Interleukin-18 does not influence infarct volume or functional outcome in the early stage after transient focal brain ischemia in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68141}, year = {2010}, abstract = {Interleukin-18 (IL-18) is a proinflammatory cytokine of the interleukin-1 family which is upregulated after cerebral ischemia. The functional role of IL-18 in cerebral ischemia is unknown. In the present study, we compared infarct size in IL-18 knock-out and wild-type mice 24 hours and 48 hours after 1-hour transient middle cerebral artery occlusion (tMCAO). Moreover, the functional outcome was evaluated in a modified Bederson score, foot fault test and grip test. There were no significant differences in infarct size or functional outcome tests between wild-type and IL-18 knock-out mice. These data indicate that the early inflammatory response to cerebral ischemia does not involve IL-18, in contrast to other interleukin-1 family members such as interleukin-1.}, subject = {Interleukin-18}, language = {en} } @article{EhlingBittnerBobaketal.2010, author = {Ehling, P. and Bittner, S. and Bobak, N. and Schwarz, T. and Wiendl, H. and Budde, T. and Kleinschnitz, Christoph and Meuth, S. G.}, title = {Two pore domain potassium channels in cerebral ischemia: a focus on K2p9.1 (TASK3, KCNK9)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68129}, year = {2010}, abstract = {BACKGROUND: Recently, members of the two-pore domain potassium channel family (K2P channels) could be shown to be involved in mechanisms contributing to neuronal damage after cerebral ischemia. K2P3.1-/- animals showed larger infarct volumes and a worse functional outcome following experimentally induced ischemic stroke. Here, we question the role of the closely related K2P channel K2P9.1. METHODS: We combine electrophysiological recordings in brain-slice preparations of wildtype and K2P9.1-/- mice with an in vivo model of cerebral ischemia (transient middle cerebral artery occlusion (tMCAO)) to depict a functional impact of K2P9.1 in stroke formation. RESULTS: Patch-clamp recordings reveal that currents mediated through K2P9.1 can be obtained in slice preparations of the dorsal lateral geniculate nucleus (dLGN) as a model of central nervous relay neurons. Current characteristics are indicative of K2P9.1 as they display an increase upon removal of extracellular divalent cations, an outward rectification and a reversal potential close to the potassium equilibrium potential. Lowering extracellular pH values from 7.35 to 6.0 showed comparable current reductions in neurons from wildtype and K2P9.1-/- mice (68.31 +/- 9.80\% and 69.92 +/- 11.65\%, respectively). These results could be translated in an in vivo model of cerebral ischemia where infarct volumes and functional outcomes showed a none significant tendency towards smaller infarct volumes in K2P9.1-/- animals compared to wildtype mice 24 hours after 60 min of tMCAO induction (60.50 +/- 17.31 mm3 and 47.10 +/- 19.26 mm3, respectively). CONCLUSIONS: Together with findings from earlier studies on K2P2.1-/- and K2P3.1-/- mice, the results of the present study on K2P9.1-/- mice indicate a differential contribution of K2P channel subtypes to the diverse and complex in vivo effects in rodent models of cerebral ischemia.}, subject = {Kaliumkanal}, language = {en} } @article{PhamHelluyBraeuningeretal.2010, author = {Pham, Mirko and Helluy, X. and Braeuninger, S. and Jakob, P. and Stoll, G. and Kleinschnitz, Christoph and Bendszus, M.}, title = {Outcome of experimental stroke in C57Bl/6 and Sv/129 mice assessed by multimodal ultra-high field MRI}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68115}, year = {2010}, abstract = {Transgenic mice bred on C57Bl/6 or Sv/129 genetic background are frequently used in stroke research. It is well established that variations in cerebrovascular anatomy and hemodynamics can influence stroke outcome in different inbred mouse lines. We compared stroke development in C57Bl/6 and Sv/129 mice in the widely used model of transient middle cerebral artery occlusion (tMCAO) by multimodal ultra-high field magnetic resonance imaging (MRI). C57Bl/6 and Sv/129 mice underwent 60 min of tMCAO and were analyzed by MRI 2 h and 24 h afterwards. Structural and functional images were registered to a standard anatomical template. Probability maps of infarction were rendered by automated segmentation from quantitative T2-relaxometric images. Whole-brain segmentation of infarction was accomplished manually on high-resolution T2-weighted (T2-w) RARE images. Cerebral perfusion (cerebral blood flow, CBF) was measured quantitatively by modified continuous arterial-spin-labeling (CASL) and apparent diffusion coefficients (ADC) by spin-echo diffusion-weighted imaging (DWI). Probabilities of cortical (95.1\% ± 3.1 vs. 92.1\% ± 2.5; p > 0.05) and subcortical (100\% vs. 100\%; p > 0.05) infarctions at 24 h were similar in both groups as was the whole-brain volumetric extent of cerebral infarction. In addition, CBF and ADC values did not differ between C57Bl/6 and Sv/129 mice at any time point or region of interest. The C57Bl/6 and Sv/129 genetic background is no major confounding factor of infarct size and cerebral perfusion in the tMCAO model.}, subject = {NMR-Tomographie}, language = {en} } @article{KraftSchwarzPochetetal.2010, author = {Kraft, P. and Schwarz, T. and Pochet, L. and Stoll, G. and Kleinschnitz, Christoph}, title = {COU254, a specific 3-carboxamide-coumarin inhibitor of coagulation factor XII, does not protect mice from acute ischemic stroke}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68103}, year = {2010}, abstract = {Background: Anticoagulation is an important means to prevent from acute ischemic stroke but is associated with a significant risk of severe hemorrhages. Previous studies have shown that blood coagulation factor XII (FXII)- deficient mice are protected from pathological thrombus formation during cerebral ischemia without bearing an increased bleeding tendency. Hence, pharmacological blockade of FXII might be a promising and safe approach to prevent acute ischemic stroke and possibly other thromboembolic disorders but pharmacological inhibitors selective over FXII are still lacking. In the present study we investigated the efficacy of COU254, a novel nonpeptidic 3-carboxamide-coumarin that selectively blocks FXII activity, on stroke development and post stroke functional outcome in mice. Methods: C57Bl/6 mice were treated with COU254 (40 mg/kg i.p.) or vehicle and subjected to 60 min transient middle cerebral artery occlusion (tMCAO) using the intraluminal filament method. After 24 h infarct volumes were determined from 2,3,5-Triphenyltetrazoliumchloride(TTC)-stained brain sections and functional scores were assessed. Hematoxylin and eosin (H\&E) staining was used to estimate the extent of neuronal cell damage. Thrombus formation within the infarcted brain areas was analyzed by immunoblot. Results: Infarct volumes and functional outcomes on day 1 after tMCAO did not significantly differ between COU254 pre-treated mice or untreated controls (p > 0.05). Histology revealed extensive ischemic neuronal damage regularly including the cortex and the basal ganglia in both groups. COU254 treatment did not prevent intracerebral fibrin(ogen) formation. Conclusions: COU254 at the given concentration of 40 mg/kg failed to demonstrate efficacy in acute ischemic stroke in this preliminary study. Further preclinical evaluation of 3-carboxamide-coumarins is needed before the antithrombotic potential of this novel class of FXII inhibitors can be finally judged.}, subject = {Schlaganfall}, language = {en} } @techreport{MagnusLinkerMeuthetal.2011, author = {Magnus, Tim and Linker, Ralf A. and Meuth, Sven G. and Kleinschnitz, Christoph and Korn, Thomas}, title = {Report on the 2nd scientific meeting of the "Verein zur Foerderung des Wissenschaftlichen Nachwuchses in der Neurologie" (NEUROWIND e.V.) held in Motzen, Germany, Oct. 29'th - Oct. 31'st, 2010}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68789}, year = {2011}, abstract = {Summary of the scientific contributions to the NEUROWIND meeting 2010: Contributions in the fields of neuroimmunology and neurodegeneration}, subject = {Wissenschaftlicher Nachwuchs}, language = {en} }