Project description:Spinal cord injury (SCI) leads to fibrotic scar formation at the lesion site, which finally affects axon regeneration and motor functional recovery. Myofibroblasts have been regarded as the main cell types that filled in the fibrotic scar, however, the cell source of myofibroblasts in transection and crush SCI model remain to be elusive. Here we used lineage tracing or single cell transcription sequencing to investigate the cell origin of fibrotic scar. We found fibrotic scars were filled from PDGFRβ+ daughter cells in spinal cord in crush SCI or transection SCI. The parenchyma perivascular-derived and meninges-derived PDGFRβ+ fibroblasts, but not PDGFRβ+ pericytes, proliferated and contributed to fibrotic cells in the lesion core. The percentage of meninges-derived fibroblasts specifically was higher than parenchyma perivascular-derived fibroblasts in transection model, which might contribute to the more fibrotic scar in transection model than crush model. These findings may provide theoretical support for the treatment of spinal cord injury.
Project description:Purpose: The goal of this study was to determine the gene expression changes that occur over 7 days in parralyzed muscle in response to isometric contraction elicited by electrical stimulation initiated 4 months after spinal cord injury and to compare such changes to those observed in a normal muscle subjected to overload. Methods: Electrical stimulation of the soleus and plantaris muscle was stimulated in female rats with complete transection of the spinal cord at the interspace between the 9th and 10th thoracic vertebrae. Stimulation was begun 16 weeks after spinal cord transection and produced near-isometric contraction of soleus, plantaris and tibialis anterior. Muscle was analyzed at 1, 2 and 7 days after starting exercise with electrical stimulation. To provide a baseline reference for gene expression at 16 weeks after spinal cord injury, muscle was also analysed from an additional group of spinal cord transected animals. One additional group of animals with a sham-spinal cord injury was included to provide information about gene expression in neurologically intact animals of similar age. In parallel studies, rats underwent bilateral gastrocnemius ablation to overload soleus and plantaris, or a sham ablation as a control. Muscle was analyzed at 1, 3 and 7 days after gastrocnemius ablation or sham-ablation. Gene expression was determined using Affymetrix Rat Exon microarrays. For each group of animals, microarray analysis was performed for soleus muscle for each of 3 separate animals, using one array per animal. Control sammples for the spinal cord injured groups included a group of animals with a Sham-spinal cord injury, and a group of spinal cord injured animals that did not get electrical stimulation. The comparator for determining fold-change expression values was the spinal cord injured group that did not receive electrical stimulation. For each day after gastrocnemius ablation, a control was included that received all procedures needed for this ablation except cutting the distal insertion of the gastrocnemius into the Achilles tendon to control for effects of the surgery on gene expression.
Project description:LncRNAs played a crucial role in the cell growth, development and some diseases relating to central nerve system.This study suggest that with regulating the LncRNAs expression level we might design novel therapy for spinalcord injury. In this dataset, we profiled the expression pattern of LncRNAs by microarray method after spinal cord injury (SCI). Through Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis seek LncRNAs potential function in the repair of spinal cord injury. Fifteen samples were analyzed. In these sample, we divided into five groups (sham operation, 1 day post-injured, 3 days post-injured, 1 week post-injued and 3 weeks post-injured) and each group contained three mice.After RNA extraction,RNA form mice in the same group were mixed by equal mass for the preparation of microarray.Compared with spinal cord without injury, the differential expression level of LncRNAs had a few changes at 1day post-injury, reached the peak at 1 week after SCI, and subsequently declined until 3 weeks post-injury. Genes with an FDR≤0.05 and a fold-change ≥2 were selected. Subsequently we analysis the significant differential expression genes.
Project description:Label-free mass spectrometry-based quantitative proteomics was applied to a larval zebrafish spinal cord injury model, which allows axon regeneration and functional recovery within two days (days post lesion; dpl) after a spinal cord transection in 3 day-old larvae (dpf). Proteomic profiling was performed of the lesion site at 1 dpl in control animals and animals with pdgfrb+ cell-specific overexpression of either zebrafish chondoradherin (chad; chad-mCherry fusion), fibromodulin a (fmoda; fmoda-mCherry fusion), lumican (lum; lum-mCherry fusion) or prolargin (prelp; prelp-mCherry fusion).
Project description:Adult zebrafish have the ability to recover from spinal cord injury and exhibit re-growth of descending axons from the brainstem to the spinal cord. We performed gene expression analysis using microarray to find damage-induced genes after spinal cord injury, which shows that Sox11b mRNA is up-regulated at 11 days after injury. However, the functional relevance of Sox11b for regeneration is not known. Here, we report that the up-regulation of Sox11b mRNA after spinal cord injury is mainly localized in ependymal cells lining the central canal and in newly differentiating neuronal precursors or immature neurons. Using an in vivo morpholino-based gene knockout approach, we demonstrate that Sox11b is essential for locomotor recovery after spinal cord injury. In the injured spinal cord, expression of the neural stem cell associated gene, Nestin, and the proneural gene Ascl1a (Mash1a), which are involved in the self-renewal and cell fate specification of endogenous neural stem cells, respectively, is regulated by Sox11b. Our data indicate that Sox11b promotes neuronal determination of endogenous stem cells and regenerative neurogenesis after spinal cord injury in the adult zebrafish. Enhancing Sox11b expression to promote proliferation and neurogenic determination of endogenous neural stem cells after injury may be a promising strategy in restorative therapy after spinal cord injury in mammals. Spinal cord injury or control sham injury was performed on adult zebrafish. After 4, 12, or 264 hrs, a 5 mm segment of spinal cord was dissected and processed (as a pool from 5 animals) in three replicate groups for each time point and treatment.
Project description:Spinal cord injured mice were treated with IL-13, IL-4 or PBS. Populations of macrophages and microglia were sorted and analyzed separately.
Project description:The study was designed to identify genes regulated after spinal transection that might contribute to regenerative growth of neurons projecting from the NMLF in Zebrafish. Zebrafish were injured by surgical transection of the spinal cord at 1 mm caudal to the brainstem-spinal cord junction (Injured). Animals receiving sham surgery (identical surgical procedures without transection) served as control (Control). The nucleus of the medial longitudinal fascicle (NMLF) was laser capture microdissected from approximately 30 frozen sections. RNA was prepared, amplified, and run on Affymetrix Zebrafish arrays. Zebrafish were used because they recover swimming function after spinal transection in about 6 weeks. The NMLF has been identified as a prominent group of neurons that descend through the site of injury in the spinal cord and that regenerate after injury. Times were selected to distinguish early events from those in the timeframe of regenerative growth.
Project description:The goal of this study was to determine gene expression changes in pdgfrb-expressing (pdgfrb+) myoseptal and perivascular cells after spinal cord lesion in larval zebrafish.
Project description:Mice lacking the developmental axon guidance molecule EphA4 have previously been shown to exhibit extensive axonal regeneration and functional recovery following spinal cord injury. To assess mechanisms by which EphA4 may modify the response to neural injury, a microarray was performed on spinal cord tissue from mice with spinal cord injury and sham injured controls. RNA was purified from spinal cords of adult EphA4 knockout and wild-type mice four days following lumbar spinal cord hemisection or laminectomy only and was hybridised to Affymetrix All-Exon Array 1.0 GeneChips. While subsequent analyses indicated that several pathways were altered in EphA4 knockout mice, of particular interest was the attenuated or otherwise altered expression of a number of inflammatory genes, including Arginase 1, expression of which was lower in injured EphA4 knockout compared to wild-type mice. Immunohistological analyses of different cellular components of the immune response were then performed in injured EphA4 knockout and wild-type spinal cords. While numbers of infiltrating CD3+ T cells were low in the hemisection model, a robust CD11b+ macrophage / microglial response was observed post-injury. There was no difference in the overall number or spread of macrophages / activated microglia in injured EphA4 knockout compared to wild-type spinal cords at two, four or fourteen days post-injury, however a lower proportion of Arginase-1 immunoreactive macrophages / activated microglia was observed in EphA4 knockout spinal cords at four days post-injury. Subtle alterations in the neuroinflammatory response in injured EphA4 knockout spinal cords may contribute to the regeneration and recovery observed in these mice following injury. Comparison was made between gene expression in wild-type and knockout samples both before and after injury. 3 replicates per group.
Project description:The aneurysm clip impact-compression model of spinal cord injury (SCI) in animals mimics the primary mechanism of SCI in human, i.e. acute impact and persisting compression; and its histo-pathological and behavioural outcomes are extensively similar to the human SCI. In order to understand the distinct molecular events underlying this injury model, an analysis of global gene expression of the acute, subacute and chronic stages of a moderate to severe injury to the rat spinal cord was conducted using a microarray gene chip approach. Rat thoracic spinal cord (T7) was injured using aneurysm clip impact-compression injury model and the epicenter area of injured spinal cord was isolated for RNA extraction and processing and hybridization on Affymetrix GeneChip arrays.