@article{UeceylerKewenigKafkeetal.2014, author = {{\"U}{\c{c}}eyler, Nurcan and Kewenig, Susanne and Kafke, Waldemar and Kittel-Schneider, Sarah and Sommer, Claudia}, title = {Skin cytokine expression in patients with fibromyalgia syndrome is not different from controls}, doi = {10.1186/s12883-014-0185-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110624}, year = {2014}, abstract = {Background Fibromyalgia syndrome (FMS) is a chronic pain syndrome of unknown etiology. There is increasing evidence for small nerve fiber impairment in a subgroup of patients with FMS. We investigated whether skin cytokine and delta opioid receptor (DOR) gene expression in FMS patients differs from controls as one potential contributor to small nerve fiber sensitization. Methods We investigated skin punch biopsies of 25 FMS patients, ten patients with monopolar depression but no pain, and 35 healthy controls. Biopsies were obtained from the lateral upper thigh and lower calf. Gene expression of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF), interleukin (IL)-6, and IL-8 and of the anti-inflammatory cytokine IL-10 was analyzed using quantitative real-time PCR and normalizing data to 18sRNA as housekeeping gene. Additionally, we assessed DOR gene expression. Results All cytokines and DOR were detectable in skin samples of FMS patients, patients with depression, and healthy controls without intergroup difference. Also, gene expression was not different in skin of the upper and lower leg within and between the groups and in FMS patient subgroups. Conclusions Skin cytokine and DOR gene expression does not differ between patients with FMS and controls. Our results do not support a role of the investigated cytokines in sensitization of peripheral nerve fibers as a potential mechanism of small fiber pathology in FMS.}, language = {en} } @article{GrohStadlerButtmannetal.2014, author = {Groh, Janos and Stadler, David and Buttmann, Mathias and Martini, Rudolf}, title = {Non-invasive assessment of retinal alterations in mouse models of infantile and juvenile neuronal ceroid lipofuscinosis by spectral domain optical coherence tomography}, doi = {10.1186/2051-5960-2-54}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110566}, year = {2014}, abstract = {Introduction The neuronal ceroid lipofuscinoses constitute a group of fatal inherited lysosomal storage diseases that manifest in profound neurodegeneration in the CNS. Visual impairment usually is an early symptom and selective degeneration of retinal neurons has been described in patients suffering from distinct disease subtypes. We have previously demonstrated that palmitoyl protein thioesterase 1 deficient (Ppt1-/-) mice, a model of the infantile disease subtype, exhibit progressive axonal degeneration in the optic nerve and loss of retinal ganglion cells, faithfully reflecting disease severity in the CNS. Here we performed spectral domain optical coherence tomography (OCT) in Ppt1-/- and ceroid lipofuscinosis neuronal 3 deficient (Cln3-/-) mice, which are models of infantile and juvenile neuronal ceroid lipofuscinosis, respectively, in order to establish a non-invasive method to assess retinal alterations and monitor disease severity in vivo. Results Blue laser autofluorescence imaging revealed increased accumulation of autofluorescent storage material in the inner retinae of 7-month-old Ppt1-/- and of 16-month-old Cln3-/- mice in comparison with age-matched control littermates. Additionally, optical coherence tomography demonstrated reduced thickness of retinae in knockout mice in comparison with age-matched control littermates. High resolution scans and manual measurements allowed for separation of different retinal composite layers and revealed a thinning of layers in the inner retinae of both mouse models at distinct ages. OCT measurements correlated well with subsequent histological analysis of the same retinae. Conclusions These results demonstrate the feasibility of OCT to assess neurodegenerative disease severity in mouse models of neuronal ceroid lipofuscinosis and might have important implications for diagnostic evaluation of disease progression and therapeutic efficacy in patients. Moreover, the non-invasive method allows for longitudinal studies in experimental models, reducing the number of animals used for research.}, language = {en} } @article{KleinschnitzGoebelMeuthetal.2014, author = {Kleinschnitz, Christoph and G{\"o}bel, Kerstin and Meuth, Sven G. and Kraft, Peter}, title = {Glatiramer acetate does not protect from acute ischemic stroke in mice}, doi = {10.1186/2040-7378-6-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110528}, year = {2014}, abstract = {Background The role of the immune system in the pathophysiology of acute ischemic stroke is increasingly recognized. However, targeted treatment strategies to modulate immunological pathways in stroke are still lacking. Glatiramer acetate is a multifaceted immunomodulator approved for the treatment of relapsing-remitting multiple sclerosis. Experimental studies suggest that glatiramer acetate might also work in other neuroinflammatory or neurodegenerative diseases apart from multiple sclerosis. Findings We evaluated the efficacy of glatiramer acetate in a mouse model of brain ischemia/reperfusion injury. 60 min of transient middle cerebral artery occlusion was induced in male C57Bl/6 mice. Pretreatment with glatiramer acetate (3.5 mg/kg bodyweight) 30 min before the induction of stroke did not reduce lesion volumes or improve functional outcome on day 1. Conclusions Glatiramer acetate failed to protect from acute ischemic stroke in our hands. Further studies are needed to assess the true therapeutic potential of glatiramer acetate and related immunomodulators in brain ischemia.}, language = {en} } @article{KleinschnitzMenclGarzetal.2013, author = {Kleinschnitz, Christoph and Mencl, Stine and Garz, Cornelia and Niklass, Solveig and Braun, Holger and G{\"o}b, Eva and Homola, Gy{\"o}rgy and Heinze, Hans-Jochen and Reymann, Klaus G. and Schreiber, Stefanie}, title = {Early microvascular dysfunction in cerebral small vessel disease is not detectable on 3.0 Tesla magnetic resonance imaging: a longitudinal study in spontaneously hypertensive stroke-prone rats}, series = {Experimental \& Translational Stroke Medicine}, journal = {Experimental \& Translational Stroke Medicine}, doi = {10.1186/2040-7378-5-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97056}, year = {2013}, abstract = {Background Human cerebral small vessel disease (CSVD) has distinct histopathologic and imaging findings in its advanced stages. In spontaneously hypertensive stroke-prone rats (SHRSP), a well-established animal model of CSVD, we recently demonstrated that cerebral microangiopathy is initiated by early microvascular dysfunction leading to the breakdown of the blood-brain barrier and an activated coagulatory state resulting in capillary and arteriolar erythrocyte accumulations (stases). In the present study, we investigated whether initial microvascular dysfunction and other stages of the pathologic CSVD cascade can be detected by serial magnetic resonance imaging (MRI). Findings Fourteen SHRSP and three control (Wistar) rats (aged 26-44 weeks) were investigated biweekly by 3.0 Tesla (3 T) MRI. After perfusion, brains were stained with hematoxylin-eosin and histology was correlated with MRI data. Three SHRSP developed terminal CSVD stages including cortical, hippocampal, and striatal infarcts and macrohemorrhages, which could be detected consistently by MRI. Corresponding histology showed small vessel thromboses and increased numbers of small perivascular bleeds in the infarcted areas. However, 3 T MRI failed to visualize intravascular erythrocyte accumulations, even in those brain regions with the highest densities of affected vessels and the largest vessels affected by stases, as well as failing to detect small perivascular bleeds. Conclusion Serial MRI at a field strength of 3 T failed to detect the initial microvascular dysfunction and subsequent small perivascular bleeds in SHRSP; only terminal stages of cerebral microangiopathy were reliably detected. Further investigations at higher magnetic field strengths (7 T) using blood- and flow-sensitive sequences are currently underway.}, language = {en} } @article{UeceylerKahnKrameretal.2013, author = {{\"U}{\c{c}}eyler, Nurcan and Kahn, Ann-Kathrin and Kramer, Daniela and Zeller, Daniel and Casanova-Molla, Jordi and Wanner, Christoph and Weidemann, Frank and Katsarava, Zaza and Sommer, Claudia}, title = {Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case-control study}, series = {BMC Neurology}, journal = {BMC Neurology}, doi = {10.1186/1471-2377-13-47}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96527}, year = {2013}, abstract = {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.}, language = {en} } @article{GunrebenGeisKleinschnitz2013, author = {Gunreben, Ignaz and Geis, Christian and Kleinschnitz, Christoph}, title = {Acute tetraparesis secondary to bilateral precentral gyral cerebral ischemia: a case report}, series = {Journal of Medical Case Reports}, journal = {Journal of Medical Case Reports}, doi = {10.1186/1752-1947-7-61}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96179}, year = {2013}, abstract = {Introduction Sudden tetraparesis represents a neurological emergency and is most often caused by traumatic spinal cord injury, spinal epidural bleeding or brainstem ischemia and less frequently by medial disc herniation or spinal ischemia. Case presentation Here we report the rare case of an 82-year-old Caucasian man who developed severe tetraparesis four days after radical cystoprostatectomy. An emergency diagnostic study for spinal cord affection was normal. Brain magnetic resonance imaging revealed acute bilateral ischemic strokes in the precentral gyri as the underlying cause. Conclusions This case report underlines the need to also consider unusual causes of tetraparesis in an emergency situation apart from spinal cord or brain stem injury in order not to leave severe symptomatology unclear and possibly miss therapeutic options.}, 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} } @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} } @article{UeceylerHaeuserSommer2011, author = {{\"U}ceyler, Nurcan and H{\"a}user, Winfried and Sommer, Claudia}, title = {Systematic review with meta-analysis: Cytokines in fibromyalgia syndrome}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69189}, year = {2011}, abstract = {Background: To perform a systematic review and meta-analysis on cytokine levels in patients with fibromyalgia syndrome (FMS). Methods: Through December 2010 we systematically reviewed the databases PubMed, MEDLINE, and PsycINFO and screened the reference lists of 22 review articles for suitable original articles. Original articles investigating cytokines in patients with FMS were included. Data were extracted by two independent authors. Differences of the cytokine levels of FMS patients and controls were summarized by standardized mean differences (SMD) using a random effects model. Study quality was assessed applying methodological scores: modified Center of Evidence Based Medicine, Newcastle-Ottawa-Scale, and W{\"u}rzburg Methodological Quality Score. Results: Twenty-five articles were included investigating 1255 FMS patients and 800 healthy controls. Data of 13/25 studies entered meta-analysis. The overall methodological quality of studies was low. The results of the majority of studies were not comparable because methods, investigated material, and investigated target cytokines differed. Systematic review of the selected 25 articles revealed that FMS patients had higher serum levels of interleukin (IL)-1 receptor antagonist, IL-6, and IL-8, and higher plasma levels of IL-8. Meta-analysis of eligible studies showed that FMS patients had higher plasma IL-6 levels compared to controls (SMD = -0.34 [-0.64, -0.03] 95\% CI; p = 0.03). The majority of investigated cytokines were not different between patients and controls. Conclusions: The pathophysiological role of cytokines in FMS is still unclear. Studies of higher quality and with higher numbers of subjects are needed.}, subject = {Fibromyalgie}, language = {en} } @article{PuschmannSommer2011, author = {Puschmann, Anne-Katrin and Sommer, Claudia}, title = {Hypervigilance or avoidance of trigger related cues in migraineurs? - A case-control study using the emotional stroop task}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69103}, year = {2011}, abstract = {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.}, subject = {Migr{\"a}ne}, language = {en} } @article{KreisslStoutWongetal.2011, author = {Kreissl, Michael C. and Stout, David B. and Wong, Koon-Pong and Wu, Hsiao-Ming and Caglayan, Evren and Ladno, Waldemar and Zhang, Xiaoli and Prior, John and Reiners, Christoph and Huang, Sung-Cheng and Schelbert, Heinrich R.}, title = {Influence of Dietary Interventions and Insulin on Myocardial, Skeletal Muscle and Brain [18F]-Fluorodeoxyglucose Kinetics in Mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68775}, year = {2011}, abstract = {Background: We evaluated the effect of insulin stimulation and dietary changes on myocardial, skeletal muscle and brain [18F]-fluorodeoxyglucose (FDG) kinetics and uptake in vivo in intact mice. Methods: Mice were anesthetized with isoflurane and imaged under different conditions: non-fasted (n = 7; "controls"), non-fasted with insulin (2 IU/kg body weight) injected subcutaneously immediately prior to FDG (n = 6), fasted (n = 5), and fasted with insulin injection (n = 5). A 60-min small-animal PET with serial blood sampling and kinetic modeling was performed. Results: We found comparable FDG standardized uptake values (SUVs) in myocardium in the non-fasted controls and non-fasted-insulin injected group (SUV 45-60 min, 9.58 ± 1.62 vs. 9.98 ± 2.44; p = 0.74), a lower myocardial SUV was noted in the fasted group (3.48 ± 1.73; p < 0.001). In contrast, the FDG uptake rate constant (Ki) for myocardium increased significantly by 47\% in non-fasted mice by insulin (13.4 ± 3.9 ml/min/100 g vs. 19.8 ± 3.3 ml/min/100 g; p = 0.030); in fasted mice, a lower myocardial Ki as compared to controls was observed (3.3 ± 1.9 ml/min/100 g; p < 0.001). Skeletal muscle SUVs and Ki values were increased by insulin independent of dietary state, whereas in the brain, those parameters were not influenced by fasting or administration of insulin. Fasting led to a reduction in glucose metabolic rate in the myocardium (19.41 ± 5.39 vs. 3.26 ± 1.97 mg/min/100 g; p < 0.001), the skeletal muscle (1.06 ± 0.34 vs. 0.34 ± 0.08 mg/min/100 g; p = 0.001) but not the brain (3.21 ± 0.53 vs. 2.85 ± 0.25 mg/min/100 g; p = 0.19). Conclusions: Changes in organ SUVs, uptake rate constants and metabolic rates induced by fasting and insulin administration as observed in intact mice by small-animal PET imaging are consistent with those observed in isolated heart/muscle preparations and, more importantly, in vivo studies in larger animals and in humans. When assessing the effect of insulin on the myocardial glucose metabolism of non-fasted mice, it is not sufficient to just calculate the SUV - dynamic imaging with kinetic modeling is necessary.}, subject = {Insulin}, language = {en} } @article{SommerRichterRogauschetal.2011, author = {Sommer, Claudia and Richter, Helmut and Rogausch, Jan P. and Frettloh, Jule and Lungenhausen, Margitta and Maier, Christoph}, title = {A modified score to identify and discriminate neuropathic pain: a study on the German version of the neuropathic pain symptom inventory (NPSI)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68716}, year = {2011}, abstract = {Background: Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain. Methods: We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles. Results: Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91\%) and acceptable specificity (70\%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct. Conclusions: The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.}, subject = {Neuralgie}, language = {en} } @article{DoerckGoebelWeiseetal.2010, author = {Doerck, Sebastian and Goebel, Kerstin and Weise, Gesa and Schneider-Hohendorf, Tilman and Reinhardt, Michael and Hauff, Peter and Schwab, Nicholas and Linker, Ralf and Maeurer, Mathias and Meuth, Sven G. and Wiendl, Heinz}, title = {Temporal Pattern of ICAM-I Mediated Regulatory T Cell Recruitment to Sites of Inflammation in Adoptive Transfer Model of Multiple Sclerosis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68565}, year = {2010}, abstract = {Migration of immune cells to the target organ plays a key role in autoimmune disorders like multiple sclerosis (MS). However, the exact underlying mechanisms of this active process during autoimmune lesion pathogenesis remain elusive. To test if pro-inflammatory and regulatory T cells migrate via a similar molecular mechanism, we analyzed the expression of different adhesion molecules, as well as the composition of infiltrating T cells in an in vivo model of MS, adoptive transfer experimental autoimmune encephalomyelitis in rats. We found that the upregulation of ICAM-I and VCAM-I parallels the development of clinical disease onset, but persists on elevated levels also in the phase of clinical remission. However, the composition of infiltrating T cells found in the developing versus resolving lesion phase changed over time, containing increased numbers of regulatory T cells (FoxP3) only in the phase of clinical remission. In order to test the relevance of the expression of cell adhesion molecules, animals were treated with purified antibodies to ICAM-I and VCAM-I either in the phase of active disease or in early remission. Treatment with a blocking ICAM-I antibody in the phase of disease progression led to a milder disease course. However, administration during early clinical remission aggravates clinical symptoms. Treatment with anti-VCAM-I at different timepoints had no significant effect on the disease course. In summary, our results indicate that adhesion molecules are not only important for capture and migration of pro-inflammatory T cells into the central nervous system, but also permit access of anti-inflammatory cells, such as regulatory T cells. Therefore it is likely to assume that intervention at the blood brain barrier is time dependent and could result in different therapeutic outcomes depending on the phase of CNS lesion development.}, subject = {Multiple Sklerose}, language = {en} } @article{KraftBenzAustinatetal.2010, author = {Kraft, Peter and Benz, Peter Michael and Austinat, Madeleine and Brede, Marc Elmar and Schuh, Kai and Walter, Ulrich and Stoll, Guido and Kleinschnitz, Christoph}, title = {Deficiency of Vasodilator-Stimulated Phosphoprotein (VASP) Increases Blood-Brain-Barrier Damage and Edema Formation after Ischemic Stroke in Mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68522}, year = {2010}, abstract = {Background: Stroke-induced brain edema formation is a frequent cause of secondary infarct growth and deterioration of neurological function. The molecular mechanisms underlying edema formation after stroke are largely unknown. Vasodilator-stimulated phosphoprotein (VASP) is an important regulator of actin dynamics and stabilizes endothelial barriers through interaction with cell-cell contacts and focal adhesion sites. Hypoxia has been shown to foster vascular leakage by downregulation of VASP in vitro but the significance of VASP for regulating vascular permeability in the hypoxic brain in vivo awaits clarification. Methodology/Principal Findings: Focal cerebral ischemia was induced in Vasp2/2 mice and wild-type (WT) littermates by transient middle cerebral artery occlusion (tMCAO). Evan's Blue tracer was applied to visualize the extent of blood-brainbarrier (BBB) damage. Brain edema formation and infarct volumes were calculated from 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain slices. Both mouse groups were carefully controlled for anatomical and physiological parameters relevant for edema formation and stroke outcome. BBB damage (p,0.05) and edema volumes (1.7 mm360.5 mm3 versus 0.8 mm360.4 mm3; p,0.0001) were significantly enhanced in Vasp2/2 mice compared to controls on day 1 after tMCAO. This was accompanied by a significant increase in infarct size (56.1 mm3617.3 mm3 versus 39.3 mm3610.7 mm3, respectively; p,0.01) and a non significant trend (p.0.05) towards worse neurological outcomes. Conclusion: Our study identifies VASP as critical regulator of BBB maintenance during acute ischemic stroke. Therapeutic modulation of VASP or VASP-dependent signalling pathways could become a novel strategy to combat excessive edema formation in ischemic brain damage.}, subject = {Vasodilatator-stimuliertes Phosphoprotein}, language = {en} } @article{KraftSchwarzMeijersetal.2010, author = {Kraft, Peter and Schwarz, Tobias and Meijers, Joost C. M. and Stoll, Guido and Kleinschnitz, Christoph}, title = {Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) Deficient Mice Are Susceptible to Intracerebral Thrombosis and Ischemic Stroke}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68519}, year = {2010}, abstract = {Background: Thrombus formation is a key step in the pathophysiology of acute ischemic stroke and results from the activation of the coagulation cascade. Thrombin plays a central role in this coagulation system and contributes to thrombus stability via activation of thrombin-activatable fibrinolysis inhibitor (TAFIa). TAFIa counteracts endogenous fibrinolysis at different stages and elevated TAFI levels are a risk factor for thrombotic events including ischemic stroke. Although substantial in vitro data on the influence of TAFI on the coagulation-fibrinolysis-system exist, investigations on the consequences of TAFI inhibition in animal models of cerebral ischemia are still lacking. In the present study we analyzed stroke development and post stroke functional outcome in TAFI-/- mice. Methodology/Principal Findings: TAFI-/- mice and wild-type controls were subjected to 60 min transient middle cerebral artery occlusion (tMCAO) using the intraluminal filament method. After 24 hours, functional outcome scores were assessed and infarct volumes weremeasured from 2,3,5-Triphenyltetrazoliumchloride (TTC)-stained brain slices. 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. Infarct volumes and functional outcomes did not significantly differ between TAFI-/- mice and controls (p.0.05). Histology revealed extensive ischemic neuronal damage regularly including the cortex and the basal ganglia in both groups. TAFI deficiency also had no influence on intracerebral fibrin(ogen) formation after tMCAO. Conclusion: Our study shows that TAFI does not play a major role for thrombus formation and neuronal degeneration after ischemic brain challenge.}, subject = {Thrombus}, language = {en} } @article{HaarmannDeissProchaskaetal.2010, author = {Haarmann, Axel and Deiss, Annika and Prochaska, Juergen and Foerch, Christian and Weksler, Babette and Romero, Ignacio and Couraud, Pierre-Olivier and Stoll, Guido and Rieckmann, Peter and Buttmann, Mathias}, title = {Evaluation of Soluble Junctional Adhesion Molecule-A as a Biomarker of Human Brain Endothelial Barrier Breakdown}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68468}, year = {2010}, abstract = {Background: An inducible release of soluble junctional adhesion molecule-A (sJAM-A) under pro-inflammatory conditions was described in cultured non-CNS endothelial cells (EC) and increased sJAM-A serum levels were found to indicate inflammation in non-CNS vascular beds. Here we studied the regulation of JAM-A expression in cultured brain EC and evaluated sJAM-A as a serum biomarker of blood-brain barrier (BBB) function. Methodology/Principal Findings: As previously reported in non-CNS EC types, pro-inflammatory stimulation of primary or immortalized (hCMEC/D3) human brain microvascular EC (HBMEC) induced a redistribution of cell-bound JAM-A on the cell surface away from tight junctions, along with a dissociation from the cytoskeleton. This was paralleled by reduced immunocytochemical staining of occludin and zonula occludens-1 as well as by increased paracellular permeability for dextran 3000. Both a self-developed ELISA test and Western blot analysis detected a constitutive sJAM-A release by HBMEC into culture supernatants, which importantly was unaffected by pro-inflammatory or hypoxia/reoxygenation challenge. Accordingly, serum levels of sJAM-A were unaltered in 14 patients with clinically active multiple sclerosis compared to 45 stable patients and remained unchanged in 13 patients with acute ischemic non-small vessel stroke over time. Conclusion: Soluble JAM-A was not suited as a biomarker of BBB breakdown in our hands. The unexpected non-inducibility of sJAM-A release at the human BBB might contribute to a particular resistance of brain EC to inflammatory stimuli, protecting the CNS compartment.}, subject = {Biomarker}, language = {en} } @article{KleinschnitzGrundWingleretal.2010, author = {Kleinschnitz, Christoph and Grund, Henrike and Wingler, Kirstin and Armitage, Melanie E. and Jones, Emma and Mittal, Manish and Barit, David and Schwarz, Tobias and Geis, Christian and Kraft, Peter and Barthel, Konstanze and Schuhmann, Michael K. and Herrmann, Alexander M. and Meuth, Sven G. and Stoll, Guido and Meurer, Sabine and Schrewe, Anja and Becker, Lore and Gailus-Durner, Valerie and Fuchs, Helmut and Klopstock, Thomas and de Angelis, Martin Hrabe and Jandeleit-Dahm, Karin and Shah, Ajay M. and Weissmann, Norbert and Schmidt, Harald H. H. W.}, title = {Post-Stroke Inhibition of Induced NADPH Oxidase Type 4 Prevents Oxidative Stress and Neurodegeneration}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68416}, year = {2010}, abstract = {Ischemic stroke is the second leading cause of death worldwide. Only one moderately effective therapy exists, albeit with contraindications that exclude 90\% of the patients. This medical need contrasts with a high failure rate of more than 1,000 pre-clinical drug candidates for stroke therapies. Thus, there is a need for translatable mechanisms of neuroprotection and more rigid thresholds of relevance in pre-clinical stroke models. One such candidate mechanism is oxidative stress. However, antioxidant approaches have failed in clinical trials, and the significant sources of oxidative stress in stroke are unknown. We here identify NADPH oxidase type 4 (NOX4) as a major source of oxidative stress and an effective therapeutic target in acute stroke. Upon ischemia, NOX4 was induced in human and mouse brain. Mice deficient in NOX4 (Nox42/2) of either sex, but not those deficient for NOX1 or NOX2, were largely protected from oxidative stress, blood-brain-barrier leakage, and neuronal apoptosis, after both transient and permanent cerebral ischemia. This effect was independent of age, as elderly mice were equally protected. Restoration of oxidative stress reversed the stroke-protective phenotype in Nox42/2 mice. Application of the only validated low-molecular-weight pharmacological NADPH oxidase inhibitor, VAS2870, several hours after ischemia was as protective as deleting NOX4. The extent of neuroprotection was exceptional, resulting in significantly improved long-term neurological functions and reduced mortality. NOX4 therefore represents a major source of oxidative stress and novel class of drug target for stroke therapy.}, subject = {Schlaganfall}, language = {en} } @article{FrerichsSirenFeuersteinetal.1992, author = {Frerichs, K. and Sir{\`e}n, Anna-Leena and Feuerstein, G. and Hallenbeck, JM}, title = {The onset of postischemic hypoperfusion in rats is precipitous and may be controlled by local neurons}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47980}, year = {1992}, abstract = {Background and Purpose: Reperfusion following transient global cerebral ischemia is characterized by an initial hyperemic phase, which precedes hypo perfusion. The pathogenesis of these flow derangements remains obscure. Our study investigates the dynamics of postischemic cerebral blood flow changes, with particular attention to the role of local neurons. Metho(Js: We assessed local cortical blood flow continuously by laser Doppler flowmetry to permit observation of any rapid flow changes after forebrain ischemia induced by four-vessel occlusion for 20 minutes in rats. To investigate the role of local cortical neurons in the regulation of any blood flow fluctuations, five rats received intracortical microinjections of a neurotoxin (10 p,g ibotenic acid in 1 p,1; 1.5-mm-depth parietal cortex) 24 hours before ischemia to induce selective and localized neuronal depletion in an area corresponding to the sampie volume of the laser Doppler probe (1 mm3 ). Local cerebral blood flow was measured within the injection site and at an adjacent control site. Results: Ischemia was followed by marked hyperemia (235 ±23\% of control, n =7), followed by secondary hypoperfusion (45±3\% of control, n=7). The transition from hyperemia to hypoperfusioo occurred not gradually but precipitously (maximal slope of flow decay: 66±6\%/min; n=7). In ibotenic acid-injected rats, hyperemia was preserved at the injection site, but the sudden decline of blood flow was abolished (maximal slope of flow decay: 5±3\%/min compared with 53±8\%/min at the control site; n=5, p