Transcriptome Sequencing of Optic Nerve in a Rat Model of Neuromyelitis Optica Spectrum Disorder-Related Optic Neuritis (NMOSD-ON)
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ABSTRACT: This study established a rat model of NMOSD-ON by injecting patient-derived AQP4+ serum into the optic nerve sheath of rats. Optic nerve tissues were collected at 24 hours and 7 days post-modeling, along with a blank control group, for transcriptome sequencing. The aim was to explore gene expression changes during the early and peak phases of NMOSD-ON pathogenesis, thereby identifying potential disease mechanisms.
Project description:Intractable neuropathic pain is recognized as a common symptom of neuromyelitis optica spectrum disorder (NMOSD). However, the underlying mechanism of NMOSD pain remains to be elucidated. Here, we established NMOSD pain model by injecting anti-AQP4 recombinant autoantibodies (AQP4-Ab) generated from NMOSD patient’s plasmablasts into rat spinal cords and confirmed the development of mechanical allodynia. AQP4-Ab mediated extracellular ATP release from astrocytes and pharmacological inhibition of ATP receptor reversed mechanical allodynia in NMOSD pain model. Furthermore, transcriptome analysis revealed microglia activation and IL-1β elevation in NMOSD spinal cord. Inhibition of microglia activation and neutralization of IL-1β also attenuated neuropathic pain in NMOSD rat model. In addition, the human CSF ATP concentration was significantly higher in the acute and remission phase of NMOSD than in multiple sclerosis and other neurological disorder patients. These findings indicate ATP, microglial activation and IL-1β secretion orchestrates the pathogenesis of NMOSD neuropathic pain.
Project description:Interventions: P:Pressure control ventilation;V:Volume control ventilation
Primary outcome(s): Diameter of optic nerve sheath
Study Design: Parallel
Project description:Reactive gliosis is a complex process that involves profound changes in gene expression. We used microarray to indentify differentially expressed genes and to investigate the molecular mechanisms of reactive gliosis in optic nerve head in response to optic nerve crush injury. C57Bl/6 female mice were 6-8 weeks old at the time of optic nerve crush surgery. The optic nerve in the left eye was crush 1 mm behind the globe for 10 seconds and the right eye served as contralateral control. The animals were allowed to recover for 1 day, 3 day, 1 week, 3 weeks and 3 months before the optic nerve heads were collected. The naive control mice did not receive any surgery in either eye. Due to the small tissue size of the mouse optic nerve head, two optic nerve heads were pooled together for each microarray chip. The left eyes and the right eyes of two mice were combined respectively to form one pair of experiment and control samples. There were five biological replicates (10 mice) for each condition.
Project description:We used optic nerve injury as a model to study early signaling events in the neuronal soma following axonal injury. Optic nerve injury results in the selective death of retinal ganglion cells (RGCs). The time course of cell death takes place over a period of days with the earliest detection of RGC death at about 48 hr post injury. We hypothesized that in the period immediately following axonal injury, there are changes in the soma that signal surrounding glia and neurons and that start programmed cell death. In the current study, we investigated early changes in cellular signaling and gene expression that occur within the first 6 hrs post optic nerve injury. We detected differences in phosphoproteins and gene expression within this time period that we used to interpret temporal events. Our studies revealed that the entire retina has been signaled by the RGC soma within 30 min after optic nerve injury and that pathways that modulate cell death are likely to be active in RGCs within 6 hrs following axonal injury Experiment Overall Design: In the treated animals, axons of the optic nerve were crushed with fine forceps for 10 sec, 1 mm posterior to the globe, under direct visualization, within an intact meningeal sheath. Controls were contralateral eyes from the same animals in each group that had not been injured. After 6 hr eyes were enucleated and processed for tissue sectionin
Project description:The optic nerve is a white matter tract that conveys visual information to the brain. A detailed investigation of the proteome of the normal human retrobulbar optic nerve may help facilitate studies of the biology and pathophysiology of the optic nerve. We conducted an in-depth proteomic analysis of optic nerve from five adults. Proteins were fractionated using SDS-PAGE. After in-gel digestion, peptides were analyzed using LC-MS/MS on an Orbitrap Elite mass spectrometer. We identified 2,711 non-redundant proteins in the human retrobulbar optic nerve, including the astrocytic marker glial fibrillary acidic protein, several proteins expressed by oligodendrocytes (laminin, proteolipid protein, and fibronectin), myelin proteins (myelin basic protein, myelin-associated glycoprotein), paranodal structural proteins (neurofascin, contactin, α, β, and γ adducins, septin 2, endophilin, ankyrin β, spectrin), proteins involved in neuronal protection and regeneration (α crytallins A and B, dedicator of cytokinesis proteins, ciliary neurotrophic factor), proteins associated with open-angle glaucoma (thioredoxin, heat shock protein-70), and proteins associated with optic neuritis (aquaporin-4). Twenty-one unambiguous protein isoforms were identified in the optic nerve.
Project description:A major risk factor for glaucomatous optic neuropathy is the level of intraocular pressure (IOP), which can lead to retinal ganglion cell axon injury and cell death. The optic nerve has a rostral unmyelinated portion at the optic nerve head followed by a caudal myelinated region. The unmyelinated region is differentially susceptible to IOP-induced damage in rodent models and in human glaucoma. While several studies have analyzed gene expression changes in the mouse optic nerve following optic nerve injury, few were designed to consider the regional gene expression differences that exist between these distinct areas. We performed bulk RNA-sequencing on the retina and on separately micro-dissected unmyelinated and myelinated optic nerve regions from naïve C57BL/6 mice, mice after optic nerve crush, and mice with microbead-induced experimental glaucoma (total = 36). Gene expression patterns in the naïve unmyelinated optic nerve showed significant enrichment of the Wnt, Hippo, PI3K-Akt, and transforming growth factor β pathways, as well as extracellular matrix–receptor and cell membrane signaling pathways, compared to the myelinated optic nerve and retina. Gene expression changes induced by both injuries were more extensive in the myelinated optic nerve than the unmyelinated region, and greater after nerve crush than glaucoma. Changes present three and fourteen days after injury largely subsided by six weeks. Gene markers of reactive astrocytes did not consistently differ between injury states. Overall, the transcriptomic phenotype of the mouse unmyelinated optic nerve was significantly different from immediately adjacent tissues, likely dominated by expression in astrocytes, whose junctional complexes are inherently important in responding to IOP elevation.
Project description:Transcriptomic changes in the pre-chiasmatic optic nerve, retrobulbar optic nerve and retina of goats 1 day after optic nerve crush injury
Project description:The advent of biologics is significantly transforming the treatment strategies for NMOSD. However, there are no biomarkers to predict relapses associated with steroid tapering. Therefore, in this study, we analyzed the immune dynamic changes due to steroid reduction. The results of this study identified peripheral blood transcriptome signatures that could lead to the creation of urgently needed NMOSD disease activity biomarkers.
Project description:Various retinal disorder such as glaucomatous, retinal ischemia reperfusion, and traumatic optic neuropathy, are involved in the pathogenesis of neurodegeneration via glutamate exicitotoxicity. However, the proteomic characteristics and modulation of the neural-microenvironment with NMDA-induced neurodegeneration in retina and optic nerve remain partly understood. We established a protein sketch of NMDA-induced injury by comparing the proteomes of the PBS-operated, NMDA-operated and control groups. We carried out mass spectrometry-based label-free quantitative proteomics to investigate the exicitotoxic neurodegeneration mechanisms and identify key proteins that regulated neural cell death related signaling pathway in retina and optic nerve spatially. Using LC-MS/MS proteomics analysis, in total, we identified 3532 proteins in retina, 2593 proteins in optic nerve. According to Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), the protein changes and energy metabolism in retina and optic nerve tissue were comprehensively evaluated.