Project description:Central nervous system (CNS) trauma and neurodegenerative disorders trigger a cascade of cellular and molecular events resulting in neuronal apoptosis and regenerative failure. The pathogenic mechanisms and gene expression changes associated with these detrimental events can be effectively studied using a rodent optic nerve crush (ONC) model. The purpose of this study was to use a mouse ONC model to: (a) evaluate changes in retina gene expression, (b) identify neurodegenerative pathogenic pathways and (c) discover potential new therapeutic targets. Affymetrix Mouse Gene 1.0 ST arrays were utlized to detail the global gene expression profile following optic nerve crush (ONC) in the retina of BALB/cJ mice at six different days post crush (dpc) (naive, 3 dpc, 7 dpc, 14 dpc, 21 dpc and 28 dpc) to understand the pathogenic responses in relation to neuronal loss and regenerative failure.
Project description:We used microarrays to analyse expression profiles of zebrafish retina after optic nerve crush to identify potential regulatory mechanisms that underpin central nerve regeneration Total RNA extracted from 4 samples (pooling 4 animals) of Zebrafish retinae after performing optic nerve crush (at day 3 post crush) vs 4 samples (pooling 4 animals) of control (unoperated) Zebrafish retinae
Project description:Central nervous system (CNS) trauma and neurodegenerative disorders trigger a cascade of cellular and molecular events resulting in neuronal apoptosis and regenerative failure. The pathogenic mechanisms and gene expression changes associated with these detrimental events can be effectively studied using a rodent optic nerve crush (ONC) model. The purpose of this study was to use a mouse ONC model to: (a) evaluate changes in optic nerve (ON) gene expression, (b) identify neurodegenerative pathogenic pathways and (c) discover potential new therapeutic targets. Affymetrix Mouse Gene 1.0 ST arrays were utlized to detail the global gene expression profile following optic nerve crush (ONC) in the ON of BALB/cJ mice at six different days post crush (dpc) (naive, 3 dpc, 7 dpc, 14 dpc, 21 dpc and 28 dpc) to understand the pathogenic responses in relation to neuronal loss and regenerative failure.
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:We used microarrays to analyse expression profiles of zebrafish retina after optic nerve crush to identify potential regulatory mechanisms that underpin central nerve regeneration
Project description:It is well-established that neurons in the adult mammalian central nervous system are terminally differentiated and, if injured, will be unable to regenerate their connections. In contrast to mammals, zebrafish and other teleosts display a robust neuroregenerative response. Following optic nerve crush (ONX), retinal ganglion cells (RGC) regrow their axons to synapse with topographically correct targets in the optic tectum, such that vision is restored in ~21 days. What accounts for these differences between teleostean and mammalian responses to neural injury is not fully understood. A time course analysis of global gene expression patterns in the zebrafish eye after optic nerve crush can help to elucidate cellular and molecular mechanisms that contribute to a successful neuroregeneration. We used microarrays to detail the global gene expression patterns underlying a successful regeneration or the optic nerve following injury. Experiment Overall Design: Microarray analysis was performed on total RNA extracted from whole eye following optic nerve crush (ONX) or sham surgery at defined intervals (4, 12, & 21 days).
Project description:We used two groups of C57BL/6J mice, one with optic nerve crush on one eye, and another with no crush as control. Three mice were subjected to optic nerve crush, with sample names 121, 113, 114 and two were used as control with sample names 118 and 119. For the optic nerve crush, a surgical peritomy was made behind and above the eyeball and the eye muscles were gently retracted to expose the optic nerve. Dumont #5 forceps (FST) were used to crush the optic nerve approximately 0.5-1 mm behind the globe without damaging retinal vessels or affecting the blood supply.
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.
