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Wild Type Mice (wild + type_mouse)
Selected AbstractsA Preliminary Study of Solid Embryonic Cerebellar Graft Survival in Adult B6CBA Lurcher Mutant and Wild Type MiceTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2009Jan Cendelín Abstract Lurcher mutant mice represent a model of olivocerebellar degeneration. They suffer from complete loss of Purkinje cells and a reduction of granule cells and inferior olive neurons. Their wild type littermates serve as healthy controls. The aim of the work was to compare solid embryonic cerebellar graft survival within a period of 9 weeks after their transplantation in adult Lurcher mutant and wild type mice of the B6CBA strain. The solid grafts were injected through a hole in the occipital bone. Host mice were sacrificed 3, 6, or 9 weeks after the transplantation and their cerebella and brain-stems were examined histologically to assess graft presence and structure. We did not find significant differences in graft survival rates between Lurcher mutant and wild type mice. The frequency of graft presence did not differ between mice examined 3, 6, and 9 weeks after the transplantation, neither in Lurchers nor in wild type mice. The grafts were of various sizes. In some cases, only small residua of the grafts were found. Nerve fiber sprouting and cell migration from the graft to the host tissue were observed more often in wild type mice than in Lurchers when examined 6 weeks after surgery. In the period 3,9 weeks after transplantation, massive dying out of the grafts was not observed despite regressive processes in some of the grafts. The degenerative changes in the Lurcher mutant cerebellum do not have strong impact on the fate of the solid cerebellar graft. Anat Rec, 292:1986,1992, 2009. © 2009 Wiley-Liss, Inc. [source] Adenosine A3 receptors regulate heart rate, motor activity and body temperatureACTA PHYSIOLOGICA, Issue 2 2010J. N. Yang Abstract Aim:, To examine the phenotype of mice that lack the adenosine A3 receptor (A3R). Methods:, We examined the heart rate, body temperature and locomotion continuously by telemetry over several days. In addition, the effect of the adenosine analogue R- N6 -phenylisopropyl-adenosine (R-PIA) was examined. We also examined heat production and food intake. Results:, We found that the marked diurnal variation in activity, heart rate and body temperature, with markedly higher values at night than during day time, was reduced in the A3R knock-out mice. Surprisingly, the reduction in heart rate, activity and body temperature seen after injection of R-PIA in wild type mice was virtually eliminated in the A3R knock-out mice. The marked reduction in activity was associated with a decreased heat production, as expected. However, the A3R knock-out mice, surprisingly, had a higher food intake but no difference in body weight compared to wild type mice. Conclusions:, The mice lacking adenosine A3 receptors exhibit a surprisingly clear phenotype with changes in diurnal rhythm and temperature regulation. Whether these effects are due to a physiological role of A3 receptors in these processes or whether they represent a role in development remains to be elucidated. [source] Histamine-1 receptor is not required as a downstream effector of orexin-2 receptor in maintenance of basal sleep/wake statesACTA PHYSIOLOGICA, Issue 3 2010M. Hondo Abstract Aim:, The effect of orexin on wakefulness has been suggested to be largely mediated by activation of histaminergic neurones in the tuberomammillary nucleus (TMN) via orexin receptor-2 (OX2R). However, orexin receptors in other regions of the brain might also play important roles in maintenance of wakefulness. To dissect the role of the histaminergic system as a downstream mediator of the orexin system in the regulation of sleep/wake states without compensation by the orexin receptor-1 (OX1R) mediated pathways, we analysed the phenotype of Histamine-1 receptor (H1R) and OX1R double-deficient (H1R,/,;OX1R,/,) mice. These mice lack OX1R-mediated pathways in addition to deficiency of H1R, which is thought to be the most important system in downstream of OX2R. Methods:, We used H1R deficient (H1R,/,) mice, H1R,/,;OX1R,/, mice, OX1R and OX2R double-deficient (OX1R,/,;OX2R,/,) mice, and wild type controls. Rapid eye movement (REM) sleep, non-REM (NREM) sleep and awake states were determined by polygraphic electroencephalographic/electromyographic recording. Results:, No abnormality in sleep/wake states was observed in H1R,/, mice, consistent with previous studies. H1R,/,;OX1R,/, mice also showed a sleep/wake phenotype comparable to that of wild type mice, while OX1R,/,; OX2R,/, mice showed severe fragmentation of sleep/wake states. Conclusion:, Our observations showed that regulation of the sleep/wake states is completely achieved by OX2R-expressing neurones without involving H1R-mediated pathways. The maintenance of basal physiological sleep/wake states is fully achieved without both H1 and OX1 receptors. Downstream pathways of OX2R other than the histaminergic system might play an important role in the maintenance of sleep/wake states. [source] The role of free fatty acids, pancreatic lipase and Ca2+ signalling in injury of isolated acinar cells and pancreatitis model in lipoprotein lipase-deficient miceACTA PHYSIOLOGICA, Issue 1 2009F. Yang Abstract Aim and methods:, Recurrent pancreatitis is a common complication of severe hypertriglyceridaemia (HTG) often seen in patients carrying various gene mutations in lipoprotein lipase (LPL). This study investigates a possible pathogenic mechanism of cell damage in isolated mouse pancreatic acinar cells and of pancreatitis in LPL-deficient and in wild type mice. Results:, Addition of free fatty acids (FFA) or of chylomicrons to isolated pancreatic acinar cells caused stimulation of amylase release, and at higher concentrations it also caused cell damage. This effect was decreased in the presence of the lipase inhibitor orlistat. Surprisingly, pancreatic lipase whether in its active or inactive state could act like an agonist by inducing amylase secretion, increasing cellular cGMP levels and converting cell damaging sustained elevations of [Ca2+]cyt to normal Ca2+ oscillations. Caerulein increases the levels of serum amylase and caused more severe inflammation in the pancreas of LPL-deficient mice than in wild type mice. Conclusion:, We conclude that high concentrations of FFA as present in the plasma of LPL-deficient mice and in patients with HTG lead to pancreatic cell damage and are high risk factors for the development of acute pancreatitis. In addition to its enzymatic effect which leads to the generation of cell-damaging FFA from triglycerides, pancreatic lipase also prevents Ca2+ overload in pancreatic acinar cells and, therefore, counteracts cell injury. [source] Electrical stimulation promotes peripheral axon regeneration by enhanced neuronal neurotrophin signalingDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2007Arthur W. English Abstract Electrical stimulation of cut peripheral nerves at the time of their surgical repair results in an enhancement of axon regeneration. Regeneration of axons through nerve allografts was used to evaluate whether this effect is due to an augmentation of cell autonomous neurotrophin signaling in the axons or signaling from neurotrophins produced in the surrounding environment. In the thy-1-YFP-H mouse, a single 1 h application of electrical stimulation at the time of surgical repair of the cut common fibular nerve results in a significant increase in the proportion of YFP+ dorsal root ganglion neurons, which were immunoreactive for BDNF or trkB, as well as an increase in the length of regenerating axons through allografts from wild type litter mates, both 1 and 2 weeks later. Axon growth through allografts from neurotrophin-4/5 knockout mice or grafts made acellular by repeated cycles of freezing and thawing is normally very poor, but electrical stimulation results in a growth of axons through these grafts, which is similar to that observed through grafts from wild type mice after electrical stimulation. When cut nerves in NT-4/5 knockout mice were electrically stimulated, no enhancement of axon regeneration was found. Electrical stimulation thus produces a potent enhancement of the regeneration of axons in cut peripheral nerves, which is independent of neurotrophin production by cells in their surrounding environment but is dependent on stimulation of trkB and its ligands in the regenerating axons themselves. © 2006 Wiley Periodicals, Inc. Develop Neurobiol 67: 158,172, 2007. [source] PRECLINICAL STUDY: Disposition of ,9 tetrahydrocannabinol in CF1 mice deficient in mdr1a P-glycoproteinADDICTION BIOLOGY, Issue 3-4 2008Laurence Bonhomme-Faivre ABSTRACT P-glycoprotein (P-gp) plays a major role in drug efflux. All the transported substrates are more or less hydrophobic and amphiphatic in nature. Being lipophilic, ,9 tetrahydrocannabinol (THC), the main cannabis component, could be a potential P-gp substrate. The aim of this project was to determine the contribution of the mdr1a gene product to THC disposition. Therefore, oral THC and digoxin (substrate test for P-gp) pharmacokinetics have been investigated in the intestinal epithelium and in the brain capillary endothelium of CF1 mdr1a (,/,) mice (mice naturally deficient in P-gp). These pharmacokinetics were compared to THC and digoxin oral pharmacokinetics in wild type mice mdr1a (+/+) (not P-gp deficient). The application of Bailer's method showed that THC total exposure measured by the area under the plasma concentration time curve was 2.17-fold higher in CF1 mice naturally deficient in P-gp than in wild type mice after oral administration of 25 mg/kg of THC, and 2.4-fold higher after oral administration of 33 µg/kg of digoxin. As a consequence, the oral bioavailability of THC and digoxin was higher in naturally P-gp-deficient mice. We concluded that P-gp limits THC oral uptake and mediates direct drug excretion from the systemic circulation into the intestinal lumen. [source] The effects of genetic and pharmacological blockade of the CB1 cannabinoid receptor on anxietyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2002J. Haller Abstract The aim of this study was to compare the effects of the genetic and pharmacological disruption of CB1 cannabinoid receptors on the elevated plus-maze test of anxiety. In the first experiment, the behaviour of CB1-knockout mice and wild-type mice was compared. In the second experiment, the cannabinoid antagonist SR141716A (0, 1, and 3 mg/kg) was administered to both CB1-knockout and wild type mice. Untreated CB1-knockout mice showed a reduced exploration of the open arms of the plus-maze apparatus, thus appearing more anxious than the wild-type animals, however no changes in locomotion were noticed. The vehicle-injected CB1-knockout mice from the second experiment also showed increased anxiety as compared with wild types. Surprisingly, the cannabinoid antagonist SR141716A reduced anxiety in both wild type and CB1 knockout mice. Locomotor behaviour was only marginally affected. Recent evidence suggests the existence of a novel cannabinoid receptor in the brain. It has also been shown that SR141716A binds to both the CB1 and the putative novel receptor. The data presented here supports these findings, as the cannabinoid receptor antagonist affected anxiety in both wild type and CB1-knockout mice. Tentatively, it may be suggested that the discrepancy between the effects of the genetic and pharmacological blockade of the CB1 receptor suggests that the novel receptor plays a role in anxiety. [source] Increase of MCP-1 (CCL2) in myelin mutant Schwann cells is mediated by MEK-ERK signaling pathwayGLIA, Issue 8 2008Stefan Fischer Abstract Macrophages are critically involved in the pathogenesis of genetically caused demyelination, as it occurs in inherited demyelinating neuropathies. On the basis of the observation that upregulation of the Schwann cell-derived chemokine MCP-1 (CCL2) is a pathologically relevant mechanism for macrophage activation in mice heterozygously deficient for the myelin component P0 (P0+/,), we posed the question of the intracellular signaling cascade involved. By using western blot analysis of peripheral nerve lysates the MAP-kinases extracellular signal-regulated kinase 1/2 (ERK1/2) and MAP kinase/ERK kinase 1/2 (MEK1/2) showed an early and constantly increasing activation in P0 mutants. Furthermore, in nerve fibers from the P0+/, mutants, Schwann cell nuclei were much more often positive for phosphorylated ERK1/2 than in nerve fibers from wild type mice. In vitro experiments using the MEK1/2-inhibitor CI-1040 decreased ERK1/2-phosphorylation and MCP-1 expression in a Schwann cell-derived cell line. Finally, systemic application of CI-1040 lead to a decreased ERK1/2-phosphorylation and substantially reduced MCP-1-production in peripheral nerves of P0+/, mutant mice. Our study identifies MEK1/2-ERK1/2 signaling as an important intracellular pathway that connects the Schwann cell mutation with the activation of pathogenetically relevant macrophages in the peripheral nerves. These findings may have important implications for the treatment of inherited peripheral neuropathies in humans. © 2008 Wiley-Liss, Inc. [source] Altered immune response to CNS viral infection in mice with a conditional knock-down of macrophage-lineage cellsGLIA, Issue 2 2006Jessica Carmen Abstract Neuroadapted Sindbis Virus (NSV) is a neuronotropic virus that causes hindlimb paralysis in susceptible mice and rats. The authors and others have demonstrated that though death of infected motor neurons occurs, bystander death of uninfected neurons also occurs and both contribute to the paralysis that ensues following infection. The authors have previously shown that the treatment of NSV-infected mice with minocycline, an inhibitor that has many functions within the central nervous system (CNS), including inhibiting microglial activation, protects mice from paralysis and death. The authors, therefore, proposed that microglial activation may contribute to bystander death of motor neurons following NSV infection. Here, the authors tested the hypothesis using a conditional knock-out of activated macrophage-lineage cells, including endogenous CNS macrophage cells. Surprisingly, ablation of these cells resulted in more rapid death and similar weakness in the hind limbs of NSV-infected animals compared with that of control animals. Several key chemokines including IL-12 and monocyte chemoattractant protein-1 (MCP-1) did not become elevated in these animals, resulting in decreased infiltration of T lymphocytes into the CNS of the knock-down animals. Either because of the decreased macrophage activation directly or because of the reduced immune cell influx, viral replication persisted longer within the nervous system in knock-down mice than in wild type mice. The authors, therefore, conclude that although macrophage-lineage cells in the CNS may contribute to neurodegeneration in certain situations, they also serve a protective role, such as control of viral replication. © 2006 Wiley-Liss, Inc. [source] Murid herpesvirus-4 induces chronic inflammation of intrahepatic bile ducts in mice deficient in gamma-interferon signallingHEPATOLOGY RESEARCH, Issue 2 2009Babunilayam Gangadharan Aim:, Infection of gamma interferon receptor defective mice with murid herpesvirus-4 also known as murine gammaherpesvirus-68 results in multi-organ fibrosis. In this paper we characterise the pathological changes occurring in the liver in this model. Methods:, Standard immunohistochemistry and in situ hybridisation techniques were used to identify the cellular changes and the presence of virus at different times post infection. Results:, In liver sections from infected gamma interferon receptor defective mice sampled on day 16 to at least day 120, 79% showed proliferating intrahepatic bile ducts associated with a chronic mononuclear cell inflammation. Only 8% of wild type mice showed similar lesions. Coincident with the inflammatory response bile duct epithelial cells were positive for arginase 1. Around day 50 post infection onwards focal fibrotic lesions appeared in approximately 30% of gamma interferon receptor defective mice resulting in destruction of intrahepatic bile ducts. In contrast to the chronic persisting inflammatory response the presence of virus infected cells were only observed between day 12,20 post-infection. Conclusion:, Infection of gamma interferon receptor defective mice with a murine gammaherpesvirus initiates a chronic persisting inflammatory response with a pathological profile similar to the human fibrotic liver disorder Primary Sclerosing Cholangitis. [source] Fibroblast growth factor receptor-3 null mice exhibit a delay in the development of oligodendrocytes and myelinationJOURNAL OF NEUROCHEMISTRY, Issue 2002R. Bansal Fibroblast growth factors (FGFs) comprise of a family of twenty-three members which bind to four receptor tyrosine kinases (R1,R4). They induce a broad spectrum of biological effects in a variety of cell types, including neurons and glia in the CNS. In oligodendrocytes (OLs), FGF-2 elicits a number of specific responses depending on their stage of development. During OL development in vitro, the expressions of FGF-receptor mRNAs are differentially regulated. R1 mRNA increases gradually along with OL maturation, whereas R3 and R2 mRNAs peak at the OL progenitor and mature OL stages, respectively, suggesting a differential roles of these receptors in OL development. R3 is also expressed by astrocytes. To determine the roles of R3 during OL development and myelination in vivo, we have employed mice lacking functional R3 (R3-null). During myelination (P7, P9, P13), reduced numbers of differentiated OLs and myelinated fibers are observed in the brains of R3 null mice compared to wild type mice. Moreover, up-regulation of glial fibrillary acidic protein-positive astrocytes is found in the cerebellum and spinal cord of R3 null mutants. However, the number of OL progenitors (PDGF-Ra), BrdU incorporation, and cell survival (TUNEL assay) are all comparable, and R3-null myelin in adult mice appears to be similar to that of wild type mice. In mixed primary cultures of post-natal R3 null brain (that have few if any neurons), OLs exhibit a delay in differentiation similar to that observed in vivo. In summary, our results elucidate regulatory roles of FGF-R3 in mouse brain, in particular with regard to its roles in the timing of OL maturation and myelin formation (MS Society, Canada, NIH NS38878-03). [source] Interleukin-1 modulates periprosthetic tissue formation in an intramedullary model of particle-induced inflammationJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2005Noah J. Epstein Abstract Interleukin-1 (IL-1) is a proinflammatory cytokine that has been implicated in wear-debris associated total joint replacement failure. We hypothesized that the absence of the IL-1 type-1 receptor would mitigate the inflammatory response to titanium particles and decrease periprosthetic inflammatory tissue in a murine intramedullary rod model. Methods: An intramedullary rod with and without commercially pure titanium particles was placed in the femora of 24 wild type mice (WT) and 24 mice lacking a functional type-1 receptor to IL-1. Femora were analyzed histologically and by ELISA of organ culture explant supernatants. Results: The presence of titanium particles in WT mice stimulated increased expression of interleukin-6 (IL-6) and macrophage chemoattractant protein-1 (MCP-1) relative to rod only controls. In contrast, IL-6 and MCP-1 expression were diminished in IL-lrl-KO mice exposed to titanium particles. Additionally, the formation of a periprosthetic fibro-inflammatory membrane in IL-lrl-KO mice was blunted at 2 weeks when compared to that in wild-type mice. Inflammatory changes and the quality of periprosthetic bone of IL-lrl-KO mice was similar to WT mice in response to titanium particles. Conclusions: These results implicate IL-1 as an important modulator in the local inflammatory response to intramedullary titanium particles. MCP-1 appears to be significantly modulated in IL-lrl-KO mice in response to titanium particles. This may be responsible, in part, for the diminished periprosthetic membrane observed in IL-lrl-KO mice at 2 weeks. Expansion of this murine model of intramedullary particle-induced inflammation to other gene targets may contribute to a more mechanistic understanding of wear-debris associated prosthesis failure. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Period 2 Gene Deletion Abolishes ,-Endorphin Neuronal Response to EthanolALCOHOLISM, Issue 9 2010Maria Agapito Background:, Ethanol exposure during early life has been shown to permanently alter the circadian expression of clock regulatory genes and the ,-endorphin precursor proopiomelanocortin (POMC) gene in the hypothalamus. Ethanol also alters the stress- and immune-regulatory functions of ,-endorphin neurons in laboratory rodents. Our aim was to determine whether the circadian clock regulatory Per2 gene modulates the action of ethanol on ,-endorphin neurons in mice. Methods:,Per2 mutant (mPer2Brdml) and wild type (C57BL/6J) mice were used to determine the effect of Per2 mutation on ethanol-regulated ,-endorphin neuronal activity during neonatal period using an in vitro mediobasal hypothalamic (MBH) cell culture model and an in vivo milk formula feeding animal model. The ,-endorphin neuronal activity following acute and chronic ethanol treatments was evaluated by measuring the peptide released from cultured cells or peptide levels in the MBH tissues, using enzyme-linked immunosorbent assay (ELISA). Results:,Per2 mutant mice showed a higher basal level of ,-endorphin release from cultured MBH cells and a moderate increase in the peptide content in the MBH in comparison with control mice. However, unlike wild type mice, Per2 mutant mice showed no stimulatory or inhibitory ,-endorphin-secretory responses to acute and chronic ethanol challenges in vitro. Furthermore, Per2 mutant mice, but not wild type mice, failed to show the stimulatory and inhibitory responses of MBH ,-endorphin levels to acute and chronic ethanol challenges in vivo. Conclusions:, These results suggest for the first time that the Per2 gene may be critically involved in regulating ,-endorphin neuronal function. Furthermore, the data revealed an involvement of the Per2 gene in regulating ,-endorphin neuronal responses to ethanol. [source] Acamprosate: Recent Findings and Future Research DirectionsALCOHOLISM, Issue 7 2008Karl Mann This article explores the mechanisms of action and the potential responder profile of acamprosate, a compound efficacious in relapse prevention of alcoholism. New evidence at the molecular and cellular level suggests that acamprosate attenuates hyper-glutamatergic states that occur during early abstinence and involves iono (NMDA)- and metabotrotropic (mGluR5) glutamate receptors along with augmented intracellular calcium release and electrophysiological changes. Thus mutant mice with enhanced glutamate levels exhibit higher alcohol consumption than wild type mice and respond better to acamprosate, demonstrating that acamprosate acts mainly on a hyper-glutamatergic system. This mode of action further suggests that acamprosate exhibits neuroprotective properties. In rats, cue-induced reinstatement behavior is significantly reduced by acamprosate treatment whereas cue-induced craving responses in alcohol-dependent patients seem not to be affected by this treatment. An ongoing study ("Project Predict") defines specific responder profiles for an individualized use of acamprosate and naltrexone. Neurophysiological as well as psychometric data are used to define 2 groups of patients: "reward cravers" and "relief cravers". While naltrexone should work better in the first group, acamprosate is hypothesized to be efficacious in the latter where withdrawal associated and/or cue induced hyper-glutamatergic states are thought to trigger relapse. Further research should target the definition of subgroups applying endophenotypic approaches, e.g. by detecting a hyperglutamatergic syndrome using MR spectroscopy. [source] A Preliminary Study of Solid Embryonic Cerebellar Graft Survival in Adult B6CBA Lurcher Mutant and Wild Type MiceTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2009Jan Cendelín Abstract Lurcher mutant mice represent a model of olivocerebellar degeneration. They suffer from complete loss of Purkinje cells and a reduction of granule cells and inferior olive neurons. Their wild type littermates serve as healthy controls. The aim of the work was to compare solid embryonic cerebellar graft survival within a period of 9 weeks after their transplantation in adult Lurcher mutant and wild type mice of the B6CBA strain. The solid grafts were injected through a hole in the occipital bone. Host mice were sacrificed 3, 6, or 9 weeks after the transplantation and their cerebella and brain-stems were examined histologically to assess graft presence and structure. We did not find significant differences in graft survival rates between Lurcher mutant and wild type mice. The frequency of graft presence did not differ between mice examined 3, 6, and 9 weeks after the transplantation, neither in Lurchers nor in wild type mice. The grafts were of various sizes. In some cases, only small residua of the grafts were found. Nerve fiber sprouting and cell migration from the graft to the host tissue were observed more often in wild type mice than in Lurchers when examined 6 weeks after surgery. In the period 3,9 weeks after transplantation, massive dying out of the grafts was not observed despite regressive processes in some of the grafts. The degenerative changes in the Lurcher mutant cerebellum do not have strong impact on the fate of the solid cerebellar graft. Anat Rec, 292:1986,1992, 2009. © 2009 Wiley-Liss, Inc. [source] Role of interleukin-1, in postoperative cognitive dysfunctionANNALS OF NEUROLOGY, Issue 3 2010Mario Cibelli MD Objective: Although postoperative cognitive dysfunction (POCD) often complicates recovery from major surgery, the pathogenic mechanisms remain unknown. We explored whether systemic inflammation, in response to surgical trauma, triggers hippocampal inflammation and subsequent memory impairment, in a mouse model of orthopedic surgery. Methods: C57BL/6J, knock out (lacking interleukin [IL]-1 receptor, IL-1R,/,) and wild type mice underwent surgery of the tibia under general anesthesia. Separate cohorts of animals were tested for memory function with fear conditioning tests, or euthanized at different times to assess levels of systemic and hippocampal cytokines and microglial activation; the effects of interventions, designed to interrupt inflammation (specifically and nonspecifically), were also assessed. Results: Surgery caused hippocampal-dependent memory impairment that was associated with increased plasma cytokines, as well as reactive microgliosis and IL-1, transcription and expression in the hippocampus. Nonspecific attenuation of innate immunity with minocycline prevented surgery-induced changes. Functional inhibition of IL-1,, both in mice pretreated with IL-1 receptor antagonist and in IL-1R,/, mice, mitigated the neuroinflammatory effects of surgery and memory dysfunction. Interpretation: A peripheral surgery-induced innate immune response triggers an IL-1,-mediated inflammatory process in the hippocampus that underlies memory impairment. This may represent a viable target to interrupt the pathogenesis of postoperative cognitive dysfunction. ANN NEUROL 2010;68:360,368 [source] Monocytes/macrophages infected with Toxoplasma gondii do not increase co-stimulatory molecules while maintaining their migratory abilityAPMIS, Issue 9 2009DANIELE SEIPEL Toxoplasma gondii is an obligate intracellular parasite that is able to disseminate into deep tissues and cross biological barriers, reaching immunoprivileged sites such as the brain and retina. The parasite is able to infect macrophages and dendritic cells and use them for dispersal throughout the body, but the activation state of those cells is unknown. We investigated the ability of human and murine cells from monocytic/macrophage lineages that had not previously been exposed to inflammatory cytokines to up-regulate co-stimulatory and adhesion molecules upon infection. Toxoplasma gondii -infected human monocytes (freshly isolated and THP1 lineage) were unable to up-regulate CD86, CD83, CD40 or CD1a. CD80 expression increased in infected cells but expression of l -selectin and ,2 integrin was unaltered. We evaluated the ability of infected macrophages from wild type C57/BL/6 or CD14,/, mice to migrate in 8 ,m transwells. Infected cells from CD14,/, mice were more likely to de-adhere than infected cells from wild type mice but they did not show any increase in migratory ability. The non-stimulatory profile of these infected cells may contribute to parasite spread throughout the lymphatic circulation in the initial phases of infection. [source] Contribution of specific binding to the central benzodiazepine site to the brain concentrations of two novel benzodiazepine site ligandsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 6 2007Andrew Pike Abstract The in vivo occupancy of brain benzodiazepine binding sites by compounds A and B was measured using a [3H]Ro 15-1788 binding assay and related to plasma and brain drug concentrations. The plasma concentration associated with 50% occupancy was higher for compound A than compound B (73 and 3.7 nM, respectively), however, there was little difference in the brain concentrations required (73 and 63 nM). Both compounds showed a non-linear relationship between plasma and brain concentrations such that above brain concentrations of ,100 nM increasing plasma concentrations did not result in a concomitant increase in brain concentrations. This is consistent with brain concentrations being dependent on a saturable compartment which was postulated to be the benzodiazepine binding site-containing GABAA receptors. This hypothesis was tested in ,1H101R mice, in which the ,1 subunit of the GABAA receptor is rendered insensitive to benzodiazepine binding resulting in an approximate 50% reduction in the total benzodiazepine-containing GABAA receptor population. It was shown that the Occ50 brain concentrations in the ,1H101R animals was lower (17 nM) than in wild type mice (63 nM), as was the plateau concentration in the brain (105 and 195 nM, respectively). These data suggest measured concentrations of compounds A and B in brain tissue are dependent on receptor expression with a minimal contribution from unbound and non-specifically bound compound. Copyright © 2007 John Wiley & Sons, Ltd. [source] The interaction between components of the fibrinolytic system and GPIb/V/IX of platelets thrombus formation in miceBRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2000Hiroyuki Matsuno The interaction of fibrinolytic components with GPIb/V/IX of platelets on thrombus formation, was investigated in mice deficient in tissue type (tPA,/,), urokinase type plasminogen activator (uPA,/,) or plasminogen activator inhibitor-1 (PAI-1,/,) and in their wild type control (tPA+/+, uPA+/+, PAI-1+/+). A thrombus was induced in the murine carotid artery using a photochemical reaction. The times to occlusion after the initiation of endothelial injury in all wild type mice was within 12 min, and no significant changes in occlusion delay were observed in uPA,/, and tPA,/, mice compared to wild type mice, whereas that of PAI-1 mice were significantly prolonged (16.9±2.9 min, P<0.05). When high molecular weight aurintricarboxylic acid (ATA), an inhibitor of platelet glycoprotein Ib/V/IX, was administered, the time to occlusion was prolonged in a dose-dependent manner in all types of mice. However, when this compound was injected in tPA,/, mice, the most significant changes were observed: i.e. the estimated ED50 was 20.2 times higher than that in tPA+/+ mice, but the estimated ED50 in uPA,/, mice was not changed as compared with that of wild type mice. On the other hand, when ATA was injected in PAI-1,/, mice, the estimated ED50 was significantly decreased (P<0.05). Platelet aggregation induced by botrocetin was not significantly different among all types of mice. The bleeding time was prolonged in a dose dependent-manner when ATA was injected in all types of mice. In conclusion, the antithrombotic effect of inhibition of platelet GPIb/V/IX is severely affected by the absence or presence of tPA-production on thrombus formation and the inhibition of PAI-1 could enhance this antithrombotic effect. British Journal of Pharmacology (2000) 131, 858,864; doi:10.1038/sj.bjp.0703639 [source] Role of ocular pigment epithelial cells in regional ocular immunityACTA OPHTHALMOLOGICA, Issue 2008S SUGITA Purpose To whether soluble factors by retinal pigment epithelial cells (RPE) promote the generation of T regulatory cells in vitro. Methods Primary cultured RPE cells were established from normal C57BL/6 mice. T cells were co-cultured with RPE, x-irradiated, and used as regulators (RPE Treg cells). Target bystander T cells were established from normal splenic T cells with anti-CD3 antibodies. T-cell activation was assessed for proliferation by [3H],thymidine incorporation. Expression of cytotoxic T lymphocyte antigen-2, (CTLA-2,) and cathepsin L on RPE and T cells was evaluated with oligonucleotide microarray, RT-PCR, immune staining, western blots and flow cytometry. Recombinant mouse CTLA-2, and anti-mouse CTLA-2, abs were used for the assay. For induction of experimental autoimmune uveitis (EAU), mice were immunized with interphotoreceptor retinoid-binding protein peptide emulsified in complete Freund's adjuvant. Results RPE converted CD4+ T cells into Treg cells by producing and secreting CTLA-2,, a cathepsin L inhibitor. CTLA-2, secreted by RPE cells selectively inhibited cathepsin L in the T cells and the cathepsin L-lacking T cells exhibited Treg phenotype, i.e. expression of Foxp3 and production of transforming growth factor beta (TGF,). CTLA-2, enhanced their production of active forms of TGF,. In addition, CD4+ T cells from EAU-induced cathepsin L knockout (KO) donors contained high population of Foxp3+ T cells and EAU in cathepsin L KO mice was significantly less than those in wild type mice. Furthermore, treatment with recombinant CTLA-2, significantly suppressed EAU. Conclusion These results indicate that immunosuppressive factors derived from RPE participate in the establishment of immune regulation in the posterior segment of the eye. [source] Keratocyte repopulation in UVB-exposed thioltransferase knockout miceACTA OPHTHALMOLOGICA, Issue 2007A PODSKOCHY Purpose: Thioltransferase is involved in cell protein homeostasis and DNA synthesis. It inhibits apoptosis and stimulates cell proliferation. Keratocyte repopulation after ultraviolet B (UVB) damage was studied in corneas of thioltransferase (-/-) mice. Methods: Six wild type mice and six thioltransferase (-/-) mice corneas were exposed at 300 nm UV-radiation at a dose producing damage in the corneal stroma (8 kJ/m2). Animals were killed 3 and 7 days after exposure. Corneas were processed for light microscopy. Results: All corneas of wild type mice and thioltransferase (-/-) mice showed extensive damage 3 days after UVB exposure. Keratocytes disappeared throughout the entire thickness of the UVB-damaged central stroma. Corneal thickness was nearly doubled compared with non-treated control corneas. However, 7 days after UVB exposure corneas of wild type mice were almost completely repopulated by keratocytes, only superficial Ľ of the stroma was still free of keratocytes. Corneal thickness was almost normal. Corneal stroma in the thioltransferase (-/-) mice 7 days after UV exposure was still not repopulated by keratocytes and the corneas were still very thick. Conclusions: The keratocyte repopulation in thioltransferase (-/-) mice is delayed. Thioltransferase seems to play an important role in the corneal wound healing and keratocyte repopulation after UVB induced damage. [source] Placental growth factor (PlGF) inhibition reduces choroidal neovascularization in a mouse model for age-related macular degenerationACTA OPHTHALMOLOGICA, Issue 2007S VAN DE VEIRE Purpose: To evaluate whether and through which mechanism PlGF blockage can inhibit choroidal neovascularization (CNV) in a mouse model of age-related macular degeneration (ARMD). Methods: CNV was induced in mice by placing 3 Argon laser burns on the choroid. In a first experiment we compared CNV formation between PlGF knock-out and wild type mice. Secondly, 144 wild-type mice were injected every 2 days with 5, 10, 20 or 40 mg/kg of either an anti-PlGF-antibody, an anti-VEGF receptor-2 (VEGFR2) antibody or an irrelevant control antibody. The CNV lesions were evaluated on histological cross-sections. The amount of endothelial cells, pericytes and inflammatory cells in the lesions were morphometrically analyzed after immunostaining for CD31, smooth muscle alpha-actin and F4/80 respectively. Results: CNV formation was significantly reduced in the PlGF knockout mice. The dose-response experiment showed that the 20 mg/kg dose of anti-PlGF significantly reduced the number of vessels in the lesions as compared to control antibody (p= 0.045), although less than a comparable dose of anti-VEGFR2 (p=0.027). Moreover, smooth muscle cell coverage was significantly increased in the anti-PlGF treated (p=0.04) and reduced in the anti-VEGFR2 treated mice (p=0.03) as compared to control mice. Finally, a significant reduction in number of inflammatory cells was observed in the lesions treated with anti-PlGF (p=0.017) but not in the anti-VEGFR2 treated mice (p=0.33). Conclusions: Anti-PlGF treatment inhibits CNV formation in a mouse model for ARMD. Both anti-PlGF and anti-VEGFR2 impair capillary growth, but in contrary to VEGFR2 blockage, anti-PlGF also reduces inflammation and promotes vessel maturation. [source] Limited humoral immunoglobulin E memory influences serum immunoglobulin E levels in bloodCLINICAL & EXPERIMENTAL ALLERGY, Issue 9 2009G. Achatz-Straussberger Summary The switch of B cells expressing membrane-bound Igs, which serve as antigen receptors, to antibody-secreting plasmablasts and finally to non-dividing, long-lived plasma cells (PCs) lacking an antigen receptor, marks the terminal differentiation of a B cell. Antibody-secreting PCs represent the key cell type for the maintenance of a proactive humoral immunological memory. Although some populations of long-lived PCs persist in the spleen, most of them return to their ,place of birth' and travel to the bone marrow or invade inflamed tissues, where they survive up to several months in survival niches as resident, immobile cells. Existing data strongly support the notion that isotype-specific receptor signalling influences the migration behaviour of plasmablasts to the bone marrow. The recent observation in the murine sytem that the immigration of plasmablasts and the final differentiation to long-lived PCs in the bone marrow is dependent on the expressed B-cell isotype and the related expression of chemokine receptors leads to the conclusion that during a T-helper type 2 (Th2)-mediated immune response in wild type mice, IgE plasmablasts do not have the same chance to contribute to long-lived PC memory as IgG1 plasmablasts. The overall limited humoral IgE memory additionally restricts the quantity of IgE Igs in the serum. [source] Investigation of Protective Reactions Against Cadmium Toxicity in the Cells Established from a Transgenic Mouse Deficient in the Metallothionein GenesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2003Tetsuya Abe Objective:, To characterize a fibroblast cell strain which we established from an metallothionein (MT) knock-out (KO) mouse and to determine whether expression of the Hsp genes induced by cadmium is related to expression of the MT-I and -II genes. Methods:, We established a fibroblast cell strain (named "MT-KO2") derived from the peritoneum of an MT-KO mouse which is deficient in the MT-I and -II genes. We determined an expression of MT-I, Hsp32 and Grp 78 genes by Northern blot analysis. Results:, The mRNA level of MT-I, an isoform of the MT gene products, was induced dose-dependently in responce to increasing concentrations of CdCl2 (5,25 µM) in a fibroblast cell strain derived from the peritoneum of an MT wild type mouse (named "MT-W3"). But it was not induced in MT-KO2 cells after the same treatment. There was no significant difference between MT-KO2 and MT-W3 cells in a concentration of intracellular glutathione (reduced form) under normal conditions. MT-KO2 cells were not more sensitive to cytotoxicity of CdCl2 than in MT-W3 cells. Expression of the Hsp32 gene was more extensively enhanced in MT-KO2 cells than in MT-W3 cells after treatment with 5,10 µM CdCl2 for 5 hours. Furthermore, the cellular concentration of reduced glatathione (GSH) was also more increased in MT-KO2 cells than in MT-W3 cells after treatment with 50 µM CdCl2 for 3 hours. Conclusions:, Expression of the Hsp32 gene tends to be increased in MT-KO2 cells in response to cadmium exposure. The expression of the Hsp32 gene and increase in the cellular concentration of GSH may be augmented to compensate for the impaired expression of the MT genes in MT-KO2 cells. [source] | |||||||||||||