Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014070 (encephalomyelitis)
13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Upregulated expression of the low-affinity neurotrophin receptor (p75) in the central nervous system (CNS) during experimental autoimmune encephalomyelitis (EAE) has recently been demonstrated. To investigate whether p75 plays a role in disease pathogenesis, we adopted a gene therapy approach, utilizing antisense oligonucleotides to downregulate p75 expression during EAE. Phosphorothioate antisense oligonucleotides (AS), nonsense oligonucleotides (NS) or phosphate buffered saline (PBS) were injected daily for 18 days after immunization of SJL/J (H-2s)-mice with myelin proteolipid protein (PLP) peptide 139-151. In the AS group, there was a statistically significant reduction in both the mean maximal disease score (1.85 in the AS, 2.94 in the NS and 2.75 in the PBS-groups, respectively, P < 0.025) and in the cumulative disease incidence ( approximately 60% in the AS group and approximately 90% in the control groups). Histological and immunohistochemical analysis showed reduced inflammation and demyelination, as well as reduced p75 expression at the blood-brain barrier (BBB) in the AS-treated mice in comparison with both control groups. There was no difference, however, in p75 expression on neural cells within the CNS between the three groups of mice. We conclude that p75 could play a proactive role in the pathogenesis of EAE and may exert its effect at the level of the BBB.
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PMID:Treatment of experimental autoimmune encephalomyelitis with antisense oligonucleotides against the low affinity neurotrophin receptor. 1070 8

Nuclear factor kappa B (NF-kappa B) is a transcription factor crucially involved in glial and neuronal function. NF-kappa B is ubiquitously distributed within the nervous system, and its inducible activity can be discerned from constitutive activity. Prototypic inducible NF-kappa B in the nervous system is composed of the DNA-binding subunits p50 and p65 complexed with an inhibitory I kappa B-alpha molecule. A number of signals from the cell surface can lead to rapid activation of NK-kappa B, thus releasing the inhibition by I kappa B. This activates translocation of NF-kappa B to the nucleus, where it binds to kappa B motifs of target genes and activates transcription. Previous findings have identified reactive oxygen intermediates (ROI) as a common denominator of NF-kappa B activating signals. More specifically, hydrogen peroxide (H2O2) might be used as second messenger in the NF-kappa B system, despite its cytotoxicity. Analysis of pathways leading to NF-kappa B activation in the nervous system has identified a number of ROI-dependent pathways such as cytokine- and neurotrophin-mediated activation, glutamatergic signal transduction, and various diseases with crucial ROI involvement (e.g., Alzheimer's disease, Parkinson's disease, experimental autoimmune encephalomyelitis, multiple sclerosis, amyotrophic lateral sclerosis, and injury). A number of NF-kappa B-specific target genes contribute to the production of ROI or are involved in detoxification of ROIs. In this review, possible mechanisms and regulatory pathways of ROI-mediated NF-kappa B activation are discussed.
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PMID:Activation of NF-kappa B by reactive oxygen intermediates in the nervous system. 1122 42

Recent evidence suggests that autoimmune reactions in the central nervous system (CNS) not only have detrimental consequences but can also be neuroprotective, and that this effect is mediated by the expression of neuronal growth factors by infiltrating leucocytes. Here we dissect these two phenomena in guinea pig myelin basic protein peptide (gpMBP 63-88)-induced experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. Real-time TaqMan polymerase chain reaction (PCR) was used to measure mRNA for the nerve growth factors, brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-3. As reference, the well-known proinflammatory mediator molecules interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha were quantified. In whole lumbar cord tissue, both the nerve growth factors and the proinflammatory cytokines, IFN-gamma and TNF-alpha, displayed similar expression patterns, peaking at the height of the disease. Among the infiltrating inflammatory cells isolated and sorted from the CNS, alphabeta+/T-cell receptor (TCR)BV8S2+, but not alphabeta+/TCRBV8S2-, recognized the encephalitogenic MBP peptide. Interestingly, these two populations displayed contrasting expression patterns of nerve growth factors and proinflammatory cytokines with higher inflammatory cytokine mRNA levels in alphabeta+/TCRBV8S2+ cells at all time intervals, whereas the levels of BDNF and NT3 were higher in alphabeta+/TCRBV8S2- cells. We conclude that a potentially important neuroprotective facet of CNS inflammation dominantly prevails within other non-MBP peptide-specific lymphoid cells and that there are independent regulatory mechanisms for neurotrophin and inflammatory cytokine expression during EAE.
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PMID:Differential expression of neurotrophic factors and inflammatory cytokines by myelin basic protein-specific and other recruited T cells infiltrating the central nervous system during experimental autoimmune encephalomyelitis. 1194 Feb 33

Recent reports indicate that autoreactive T cells may produce neurotrophic factors capable of mediating repair and regeneration of damaged neurons. By using semiquantitative RT-PCR, we examined gene expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and the trkB BDNF receptor in autoreactive T cells from SWXJ mice immunized with the p104-117 encephalitogen of myelin proteolipid protein (PLP 104-117). We observed antigen-inducible expression of NGF and BDNF, but not NT-3 and trkB, in lymph node cells activated with PLP 104-117. To determine which leukocyte subpopulation expressed neurotrophins, CD4(+), CD8(+), B220(+), CD11b(+), and NK1.1(+) cells were purified from activated primary cultures, and their mRNAs were analyzed. Neurotrophin expression was also measured in CD3(+) T cells purified from mouse CNS during acute onset of experimental autoimmune encephalomyelitis as well as in resting and activated human T cells and B cells purified from peripheral blood of normal subjects. In all cases, we found that neurotrophin expression was confined exclusively to B cells (B220(+)) in both mouse and human. CD3(+), CD4(+), and CD8(+) T cells as well as NK1.1(+) cells and CD11b(+) monocytes and macrophages did not express any detectable BDNF, NGF, NT-3, or trkB under any conditions. Our data indicate that B cells rather than T cells are the predominant if not the only source of leukocyte-derived neurotrophins and as such may provide "protective autoimmunity" in repair and regeneration of the injured nervous system.
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PMID:Human and murine lymphocyte neurotrophin expression is confined to B cells. 1535 17

Complement is implicated in the pathogenesis of inflammatory disorders of the central nervous system (CNS), like multiple sclerosis, Alzheimer's disease, and trauma. The anaphylatoxins C3a and C5a are thought to be the major contributors to complement-mediated inflammation in the CNS, likely mediating their effects via their ability to attract and activate leukocytes and common capacity to augment inflammation. For example, in experimental autoimmune encephalomyelitis, the animal model of multiple sclerosis, CNS-specific expression of C3a in C3a/GFAP transgenic mice renders them prone to massive cellular infiltration of the CNS and increases their mortality. In contrast, other studies have suggested that C3a can function in an anti-inflammatory fashion in the CNS, by inducing neurotrophin production and preventing NMDA-mediated neurotoxicity. To further investigate the seemingly paradoxical role of C3a in acute inflammation of the brain, we studied the pathogenesis of endotoxin shock in C3a/GFAP transgenic, C3a receptor-deficient (C3aR-/-) and C3a/GFAPxC3aR-/- mutant mice. Here we report that C3a/GFAP mice were significantly more resistant to endotoxin-induced lethality than wild-type and C3aR-/- mice. Surprisingly, C3a/GFAPxC3aR-/- hybrids were also significantly protected, indicating that C3a exerts its protective anti-inflammatory effect either directly or via an as yet unidentified non-canonical C3aR.
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PMID:C3a expressed in the central nervous system protects against LPS-induced shock. 1608 60

We have shown earlier that induction of experimental autoimmune encephalomyelitis (EAE)-a model for the human disease multiple sclerosis-in C57BL/6 wild-type mice resulted in the expression of the p75 low-affinity neurotrophin receptor (p75NTR) in endothelial cells in the CNS. In comparison to the clinical manifestation of EAE observed in wild-type C57BL/6 mice, C57BL/6 mice deficient for p75NTR (p75NTR knockout mice) developed a more severe or even lethal disease and concomitant increased levels of inflammation in the CNS. In order to elucidate the role of endothelial p75NTR in cellular infiltration under these pathological circumstances, we have performed a more detailed, quantitative examination of the composition of the cellular infiltrate invading the CNS in EAE wild-type and EAE p75NTR knockout mice. We compared spinal cords of EAE wild-type with those of EAE p75NTR knockout mice of the same clinical score (3.5) using immunohistochemical markers for the cell types present in the infiltratory cuffs in EAE: T-cells, B-cells, monocytes, microglia, resident and infiltrating macrophages and polymorphonuclear cells. Interestingly, we detected that the proportion of B-cells, cells of the monocyte-macrophage lineage and polymorphonuclear cells in the infiltratory cuff of EAE-p75NTR knockout mice was decreased at the account of the proportion of T-cells which appeared to be almost doubled in comparison to the EAE wild-type mice. The altered composition of the infiltrate in p75NTR deficient mice argues for an involvement of endothelial p75NTR in the interaction between the inflamed endothelium and the activated cells of the immune system, in particular the T-cells, in EAE.
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PMID:Deficient p75 low-affinity neurotrophin receptor expression does alter the composition of cellular infiltrate in experimental autoimmune encephalomyelitis in C57BL/6 mice. 1651 50

Multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) result in inflammatory white matter lesions in the CNS. However, information is sparse with regard to the effects of autoimmune demyelinating disease on gray matter regions. Therefore, we studied the late effects of chronic EAE in C57BL/6 mice on the spinal cord gray matter using immunohistochemistry. Here, EAE induced marked astrocytic, microglial, and macrophage activation in the ventral horn gray matter, without any motoneuron loss. Activated caspase-3 was also increased in the ventral horn gray matter. Furthermore, activated poly (ADP-ribose) polymerase (PARP), another apoptotic marker, co-localized with myelin basic protein (MBP) of oligodendrocyte processes, but not with the oligodendroglial cell body marker, adenomatous polyposis coli gene clone CC1 (APC-CC1), or with neurofilament marker (RT-97) or synaptophysin of axonal arbors. However, there was no associated increase in the number of terminal deoxynucleotidyl transferase (TdT) mediated-dUTP nick end labeling positive nuclei in the spinal cord gray matter of EAE mice. In addition, co-localization of MBP and the low-affinity neurotrophin receptor, p75, was demonstrated, further supporting the notion of apoptotic oligodendrocyte process degeneration in the gray matter of EAE mice.
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PMID:Glial reactions and degeneration of myelinated processes in spinal cord gray matter in chronic experimental autoimmune encephalomyelitis. 1871 11

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, is neuroprotective in animal models of neurodegenerative diseases. However, BDNF has a short half-life and its efficacy in the central nervous system (CNS), when delivered peripherally, is limited due to the blood-brain barrier (BBB). We have developed a means of delivering BDNF into the CNS using genetically engineered bone marrow stem cells (BMSCs) as a vehicle, and have explored the clinical effects of BDNF on outcomes in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). BDNF-engineered-BMSCs were transplanted (i.v.) into irradiated 2-week-old SJL/J female mice. Eight weeks after transplantation, mice were immunized with a peptide of proteolipid protein (PLP(139-151)). Mice, which had received BDNFengineered BMSCs, showed a significant delay in EAE onset and a reduction in overall clinical severity compared to mice receiving BMSC transfected with an empty vector lacking the BDNF gene. In addition, pathological examination showed that BDNF delivery reduced demyelination and increased remyelination. Inhibition of pro-inflammatory cytokines TNF-alpha and IFN-gamma and enhanced expression of the antiinflammatory cytokines IL-4, IL-10, and IL-11 were found in the CNS tissues of the BDNF transplanted group. These results support the use of BMSCs as vehicles to deliver BDNF into the CNS of EAE animals. This is a potentially novel therapeutic approach that might be used to deliver BDNF gene or genes for other therapeutic proteins into the CNS in MS or in other diseases of the CNS in which accessibility of therapeutic proteins is limited due to the BBB.
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PMID:Brain-derived neurotrophic factor gene delivery in an animal model of multiple sclerosis using bone marrow stem cells as a vehicle. 1936 71

Neuromyelitis optica (NMO) is characterized by concurrence of optic neuritis and transverse myelitis, which is typically associated with a spinal cord lesion extending three or more vertebral segments. NMO is an inflammatory, demyelinating central nervous system disorder, and although it has a relapsing course in more than 90% of patients, it differs from multiple sclerosis in that it is more severe, usually spares the brain, and is associated with a longitudinally extensive lesion on spinal cord magnetic resonance imaging (MRI). Furthermore, NMO is associated with a highly specific serum marker called anti-aquaporin-4 antibody, which is believed to have a central pathogenetic role in NMO. Treatment with B-cell specific monoclonal antibody (rituximab) and plasma exchanges appears to reduce the severity and frequency of attacks in NMO, and therefore, B-cell autoimmunity as well as a humoral mechanism may be involved in the pathogenesis of NMO. Glatiramer acetate (GA; also known as Copaxone, COP-1) is a synthetic copolymer of a pool of peptides composed of random sequences of four amino acids: glutamine, lysine, alanine, and tyrosine. GA-specific T-helper 1- (Th1) and 2-type (Th2) cells produce brain-derived neurotrophic factor (BDNF), which may affect neuronal survival and myelin repair. GA treatment also leads to sustained augmentation of BDNF, neurotrophin (NT)-3, and NT-4 expression in various brain regions as demonstrated by histological analysis of immunostained brain sections and BDNF elevation after GA treatment on both protein and mRNA levels. GA-Th2 activation may also have a neuroprotective role in the course of NMO. Furthermore, B cells from GA-treated mice suppress experimental autoimmune encephalomyelitis. The pathogenesis of NMO is largely unknown. However, there is some evidence that B-cell autoimmunity, activation of eosinophils, and B-cell activating factor play important roles, based on neurotrophic factors, neuroprotection, anti-inflammation, and B-cell modulation, GA is thus a hypothetic potential treatment agent for NMO.
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PMID:Glatiramer acetate could be a hypothetical therapeutic agent for neuromyelitis optica. 2139 45

Neurotrophin growth factors support neuronal survival and function. In this study, we show that the expression of the neurotrophin receptor TrkB is induced on astrocytes in white matter lesions in multiple sclerosis (MS) patients and mice with experimental autoimmune encephalomyelitis (EAE). Surprisingly, mice lacking TrkB specifically in astrocytes were protected from EAE-induced neurodegeneration. In an in vitro assay, astrocytes stimulated with the TrkB agonist brain-derived neurotrophic factor (BDNF) released nitric oxide (NO), and conditioned medium from activated astrocytes had detrimental effects on the morphology and survival of neurons. This neurodegenerative process was amplified by NO produced by neurons. NO synthesis in the central nervous system during EAE depended on astrocyte TrkB. Together, these findings suggest that TrkB expression on astrocytes may represent a new target for neuroprotective therapies in MS.
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PMID:Stimulation of the neurotrophin receptor TrkB on astrocytes drives nitric oxide production and neurodegeneration. 2239 27


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