Initiation and progression of axonopathy in experimental autoimmune encephalomyelitis.
Ontology highlight
ABSTRACT:
SUBMITTER: Soulika AM
PROVIDER: S-EPMC2990681 | biostudies-literature | 2009 Nov
REPOSITORIES: biostudies-literature
Publications
Initiation and progression of axonopathy in experimental autoimmune encephalomyelitis.
Soulika Athena M AM Lee Eunyoung E McCauley Erica E Miers Laird L Bannerman Peter P Pleasure David D
The Journal of neuroscience : the official journal of the Society for Neuroscience 20091101 47
Axonal loss is the principal cause of chronic disability in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). In C57BL/6 mice with EAE induced by immunization with myelin oligodendrocyte glycoprotein peptide 35-55, the first evidences of axonal damage in spinal cord were in acute subpial and perivascular foci of infiltrating neutrophils and lymphocytes and included intra-axonal accumulations of the endovesicular Toll-like receptor TLR8, and the inflammasome protein NAcht le ...[more]
Similar Datasets
Project description:Voltage-gated K(+) (Kv) channels play critical roles not only in regulating synaptic transmission and intrinsic excitability of neurons, but also in controlling the function and proliferation of other cells in the central nervous system (CNS). The non-specific Kv channel blocker, 4-AminoPyridine (4-AP) (Dalfampridine, Ampyra®), is currently used to treat multiple sclerosis (MS), an inflammatory demyelinating disease. However, little is known how various types of Kv channels are altered in any inflammatory demyelinating diseases. By using established animal models for MS, experimental autoimmune encephalomyelitis (EAE), we report that expression and distribution patterns of Kv channels are altered in the CNS correlating with EAE severity. The juxtaparanodal (JXP) targeting of Kv1.2/Kv?2 along myelinated axons is disrupted within demyelinated lesions in the white matter of spinal cord in EAE. Moreover, somatodendritic Kv2.1 channels in the motor neurons of lower spinal cord significantly decrease correlating with EAE severity. Interestingly, Kv1.4 expression surrounding lesions is markedly up-regulated in the initial acute phase of both EAE models. Its expression in glial fibrillary acidic protein (GFAP)-positive astrocytes further increases in the remitting phase of remitting-relapsing EAE (rrEAE), but decreases in late chronic EAE (chEAE) and the relapse of rrEAE, suggesting that Kv1.4-positive astrocytes may be neuroprotective. Taken together, our studies reveal myelin-dependent and -independent alterations of Kv channels in the progression of EAE and lay a solid foundation for future study in search of a better treatment for MS.
| S-EPMC3367054 | biostudies-literature
Project description:Myelin-associated inhibitory factors within the central nervous system (CNS) are considered to be one of the main obstacles for axonal regeneration following disease or injury. The nogo receptor 1 (NgR1) has been well documented to play a key role in limiting axonal regrowth in the injured and diseased mammalian CNS. However, the role of nogo receptor in immune cell activation during CNS inflammation is yet to be mechanistically elucidated. Microglia/macrophages are immune cells that are regarded as pathogenic contributors to inflammatory demyelinating lesions in multiple sclerosis (MS). In this study, the animal model of MS, experimental autoimmune encephalomyelitis (EAE) was induced in ngr1+/+ and ngr1-/- female mice following injection with the myelin oligodendrocyte glycoprotein (MOG35-55) peptide. A fate-map analysis of microglia/macrophages was performed throughout spinal cord sections of EAE-induced mice at clinical scores of 0, 1, 2 and 3, respectively (increasing locomotor disability) from both genotypes, using the CD11b and Iba1 cell markers. Western immunoblotting using lysates from isolated spinal cord microglia/macrophages, along with immunohistochemistry and flow cytometric analysis, was performed to demonstrate the expression of nogo receptor and its two homologs during EAE progression. Myelin protein engulfment during EAE progression in ngr1+/+ and ngr1-/- mice was demonstrated by western immunblotting of lysates from isolated spinal cord microglia/macrophages, detecting levels of Nogo-A and MOG. The numbers of M1 and M2 microglia/macrophage phenotypes present in the spinal cords of EAE-induced ngr1+/+ and ngr1-/- mice, were assessed by flow cytometric analysis using CD38 and Erg-2 markers. A significant difference in microglia/macrophage numbers between ngr1+/+ and ngr1-/- mice was identified during the progression of the clinical symptoms of EAE, in the white versus gray matter regions of the spinal cord. This difference was unrelated to the expression of NgR on these macrophage/microglial cells. We have identified that as EAE progresses, the phagocytic activity of microglia/macrophages with myelin debris, in ngr1-/- mice, was enhanced. Moreover, we show a modulation from a predominant M1-pathogenic to the M2-neurotrophic cell phenotype in the ngr1-/- mice during EAE progression. These findings suggest that CNS-specific macrophages and microglia of ngr1-/- mice may exhibit an enhanced capacity to clear inhibitory molecules that are sequestered in inflammatory lesions.
| S-EPMC5998626 | biostudies-literature
Project description:AimThe purpose of this investigation was to further explore the mechanism(s) underlying the amelioration in EAE caused by Fasudil, particularly focusing on anti-inflammatory effect.MethodsWe induced a chronic-progressive experimental autoimmune encephalomyelitis (EAE) in B6 mice immunized with myelin oligodendrocyte glycoprotein(35-55) and performed Fasudil intervention in early and late stages of the disease.ResultsThe administration of Fasudil (40 mg/kg, i.p) had a therapeutic effect in delaying the onset and ameliorating the severity of EAE, accompanied by the improvement in myelination and the decrease in inflammatory cells in spinal cords. Fasudil inhibited TLR-4, p-NF-kB/p65, and inflammatory cytokines (IL-1?, IL-6, and TNF-?) and enhanced IL-10 production in spinal cords. The ratio of arginase/iNOS was enhanced mainly in the spinal cords of EAE mice treated with Fasudil, reflecting a shift toward the M2 (antiinflammation) macrophage/microglia phenotype. The administration of Fasudil also induced the upregulation of CB2 receptor in spinal cords, but did not significantly trigger CB1 receptor. Levels of neurotrophic factors NGF, BDNF, and GDNF in the CNS were not altered by Fasudil.ConclusionFasudil ameliorates disease progression in EAE, acting possibly through antiinflammatory pathway.
| S-EPMC6493591 | biostudies-literature
Project description:NOD mice (8- to 13-wk-old) were bred and maintained at the La Trobe University Central Animal House (Bundoora, Melbourne, Australia). All experiments were conducted in accordance with the Australian code of practice for the care and use of animals for scientific purposes (National Health and Medical Research Council 1997), after approval by the La Trobe University Animal Ethics committee (Melbourne, Australia). A total of 124 female mice were divided into three groups. The immunized group comprised 91 mice injected s.c. into the lower flanks with 200 micrograms of MOG35-55 peptide (MEVGWYRSPFSRVVHLYRNGK; Auspep) emulsified in CFA containing 4 mg/ml Mycobacterium tuberculosis (Difco). An i.v. injection of 350 ng of Bordetella pertussis toxin was administered both immediately thereafter and 48 h later. The 26 mice in the control group were injected with adjuvant and pertussis toxin only. The seven animals used for the baseline group (time, day 0) were naive, not injected mice. Except for the seven naive animals from the baseline group, nine animals (seven from the EAE and two from the control group) were sacrificed (at the same time of the day) at each of 13 time points after immunization, which are detailed as days 3, 5, 7, 9, 11, 12, 13, 14, 15, 16, 17, 18, and 19 postimmunization. Lymph nodes from the remaining four animals of the immunized and from the two control groups were dissected, immersed in RNAlater (Ambion), and frozen at 20C. Lymph nodes were removed from RNAlater and homogenized in TRIzol (Invitrogen Life Technologies) using an electric homogenizer. After resuspending the final RNA pellet in water, samples were repurified using the RNeasy kit (Qiagen). cDNA was synthesized from 15 micrograms of total RNA using Superscript II RT (Invitrogen Life Technologies) and a modified dNTP mix containing dUTP. Samples were hydrolyzed by adding 10 microliters of 0.1 N NaOH, neutralized with 25 microliters of 1 M HEPES, and precipitated with 3 M sodium acetate and ethanol. Resuspension in 0.05 M sodium bicarbonate was followed by 1 h incubation with either N-hydroxysuccinimide ester Cy3 or Cy5 fluorescent dyes (Amersham Biosciences). Probes were quenched by the addition of 4 M hydroxylamine and neutralized with 100 mM sodium acetate. Final probe cleanup was conducted using the QIA Quick PCR purification kit (Qiagen). We followed a common reference design in which each Cy3-labeled lymph node probe was combined with a Cy5-labeled probe derived from a pool of RNA. Hybridization onto glass slides containing 18,240 spotted 60- to 70-mer oligonucleotides, followed by washing and scanning was performed at the Gladstone microarray core facility at the University of California (San Francisco, CA) Keywords: Time series NOD mice (8- to 13-wk-old) were injected s.c. into the lower flanks with 200 micrograms of MOG35–55 peptide (MEVGWYRSPFSRVVHLYRNGK; Auspep) emulsified in CFA containing 4 mg/ml Mycobacterium tuberculosis (Difco). An i.v. injection of 350 ng of Bordetella pertussis toxin was administered both immediately thereafter and 48 h later. The mice in the control group were injected with adjuvant and pertussis toxin only. Disease and control mice were sacrificed at 13 identical timepoints and microarrays were processed for each timepoint.
2008-04-03 | E-GEOD-7461 | biostudies-arrayexpress
Project description:Microbiome composition studies are increasingly shedding light on animal models of disease. This paper describes a protocol for analyzing the gut microbiome composition prior to and after the induction of mice to experimental autoimmune encephalomyelitis (EAE), the principal animal model of the human neuroinflammatory demyelinating disease multiple sclerosis (MS). We also address and provide data assessing the impact of mice reared in different animal facilities on EAE induction. Furthermore, we discuss potential regulators of the gut-microbiome-brain axis (GMBA) in relation to neuroinflammation and implications on demyelinating disease states. Our results suggest that mice reared in different animal facilities produce different levels of EAE induction. These results highlight the importance of accounting for consistent environmental conditions when inducing EAE and other animal models of disease. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Study of the composition of the gut microbiome in the neuroinflammatory model of experimental autoimmune encephalomyelitis Basic Protocol 2: Experimental procedures for DNA extraction and microbiome analysis.
| S-EPMC9540342 | biostudies-literature
Project description:Multiple sclerosis (MS) is the most common inflammatory disease of the central nervous system (CNS) most likely caused by autoreactive T cells. Mucosal-associated invariant T (MAIT) cells are characterized by a semi-invariant T cell receptor (TCR) with which they recognize 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil (5-OP-RU), a metabolite of the riboflavin (vitamin B2) pathway only present in yeast and bacteria. MAIT cells have been detected in inflamed brain lesions of MS patients. However, functional analyses of CNS-infiltrating MAIT cells are lacking and require a characterisation in the MS animal model experimental autoimmune encephalomyelitis (EAE).
2024-09-30 | GSE234291 | GEO
Project description:Multiple sclerosis (MS) is an autoimmune, neurodegenerative disease but the molecular mechanisms underlying neurodegenerative aspects of the disease are poorly understood. microRNAs (miRNAs) are powerful regulators of gene expression that regulate numerous mRNAs simultaneously and can thus regulate programs of gene expression. Here, we describe miRNA expression in neurons captured from mice subjected to experimental autoimmune encephalomyelitis (EAE), a model of central nervous system (CNS) inflammation. Lumbar motor neurons and retinal neurons were laser captured from EAE mice and miRNA expression was assessed by next-generation sequencing and validated by qPCR. We describe 14 miRNAs that are differentially regulated in both neuronal subtypes and determine putative mRNA targets though in silico analysis. Several upregulated neuronal miRNAs are predicted to target pathways that could mediate repair and regeneration during EAE. This work identifies miRNAs that are affected by inflammation and suggests novel candidates that may be targeted to improve neuroprotection in the context of pathological inflammation.
| S-EPMC6128870 | biostudies-other
Project description:Focal cerebral ischemia and traumatic brain injury induce an escalating amount of cell death because of harmful mediators diffusing from the original lesion site. Evidence suggests that healthy cells surrounding these lesions attempt to protect themselves by producing endocannabinoids (eCBs) and activating cannabinoid receptors, the molecular target for marijuana-derived compounds. Indeed, activation of cannabinoid receptors reduces the production and diffusion of harmful mediators. Here, we provide evidence that an exception to this pattern is found in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. We show that cell damage induced by EAE does not lead to increase in eCBs, even though cannabinoid receptors are functional because synthetic cannabinoid agonists are known to confine EAE-induced lesions. This lack of eCB increase is likely due to IFN-gamma, which is released by primed T cells invading the CNS. We show that IFN-gamma disrupts the functionality of purinergic P2X7 receptors, a key step controlling eCB production by microglia, the main source of eCBs in brain. Accordingly, induction of EAE in P2X7-/- mice results in even lower eCB levels and more pronounced cell damage than in wild-type mice. Our data suggest that the high level of CNS IFN-gamma associated with EAE disrupts eCB-mediated neuroprotection while maintaining functional cannabinoid receptors, thus providing additional support for the use of cannabinoid-based medicine to treat multiple sclerosis.
| S-EPMC1458883 | biostudies-other
Project description:OBJECTIVE: Multiple sclerosis (MS) is the most common disabling neurological disease of young adults. The pathophysiological mechanism of MS remains largely unknown and no cure is available. Current clinical treatments for MS modulate the immune system, with the rationale that autoimmunity is at the core of MS pathophysiology. METHODS: Experimental autoimmune encephalitis (EAE) was induced in mice with MOG35-55 and clinical scoring was performed to monitor signs of paralysis. EAE mice were injected intraperitoneally with TAT-fusion peptides daily from day 10 until day 30 after immunization, and their effects were measured at day 17 or day 30. RESULTS: We report a novel target for the development of MS therapy, which aimed at blocking glutamate-mediated neurotoxicity through targeting the interaction between the AMPA (2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl) propanoic acid) receptor and an interacting protein. We found that protein complex composed of the GluR2 subunit of AMPA receptors and GAPDH (glyceraldehyde-3-phosphate dehydrogenase) was present at significantly higher levels in postmortem tissue from MS patients and in EAE mice, an animal model for MS. Next, we developed a peptide that specifically disrupts the GluR2 -GAPDH complex. This peptide greatly improves neurological function in EAE mice, reduces neuron death, rescues demyelination, increases oligodendrocyte survival, and reduces axonal damage in the spinal cords of EAE mice. More importantly, our peptide has no direct suppressive effect on naive T-cell responses or basal neurotransmission. INTERPRETATION: The GluR2 -GAPDH complex represents a novel therapeutic target for the development of medications for MS that work through a different mechanism than existing treatments.
| S-EPMC4402084 | biostudies-other
Project description:BackgroundMultiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) characterized by inflammation, demyelination and axonal pathology. Myelin basic protein/proteolipid protein (MBP-PLP) fusion protein MP4 is capable of inducing chronic experimental autoimmune encephalomyelitis (EAE) in susceptible mouse strains mirroring diverse histopathological and immunological hallmarks of MS. Lack of human tissue underscores the importance of animal models to study the pathology of MS.MethodsTwenty-two female C57BL/6 (B6) mice were immunized with MP4 and the clinical development of experimental autoimmune encephalomyelitis (EAE) was observed. Methylene blue-stained semi-thin and ultra-thin sections of the lumbar spinal cord were assessed at the peak of acute EAE, three months (chronic EAE) and six months after onset of EAE (long-term EAE). The extent of lesional area and inflammation were analyzed in semi-thin sections on a light microscopic level. The magnitude of demyelination and axonal damage were determined using electron microscopy. Emphasis was put on the ventrolateral tract (VLT) of the spinal cord.ResultsB6 mice demonstrated increasing demyelination and severe axonal pathology in the course of MP4-induced EAE. Additionally, mitochondrial swelling and a decrease in the nearest neighbor neurofilament distance (NNND) as early signs of axonal damage were evident with the onset of EAE. In semi-thin sections we observed the maximum of lesional area in the chronic state of EAE while inflammation was found to a similar extent in acute and chronic EAE. In contrast to the well-established myelin oligodendrocyte glycoprotein (MOG) model, disease stages of MP4-induced EAE could not be distinguished by assessing the extent of parenchymal edema or the grade of inflammation.ConclusionsOur results complement our previous ultrastructural studies of B6 EAE models and suggest that B6 mice immunized with different antigens constitute useful instruments to study the diverse histopathological aspects of MS.
| S-EPMC4676607 | biostudies-literature