Project description:Sciatic nerve crush (SNC) triggers sterile inflammation within the distal nerve and de-afferented dorsal root ganglia (DRGs). In the nerve, neutrophils and pro-inflammatory Ly6Chigh monocytes appear first and rapidly give way to Ly6Clow resolving macrophages. Transcriptional profiling of injured nerve tissue identifies six macrophage subpopulations, repair Schwann cells and mesenchymal cells as the main cell types. Macrophages at the nerve crush site are distinct from macrophages associated with degenerating nerve fibers. Monocytes and macrophages in the injured nerve “eat” apoptotic cell corpses of leukocytes and thereby contribute to an anti-inflammatory milieu. Studies with chimeric mice show that following SNC few blood-derived immune cells enter DRGs. Myeloid cells in the injured nerve, but not DRGs, express the receptor for the chemokine GM-CSF. In the absence of GM-CSF, conditioning-lesion induced regeneration of DRG neuron central projections is abrogated. Thus, a carefully orchestrated immune response in the nerve is required for conditioning-lesion induced neurorepair.
Project description:Changes in microRNA (miRNA) expression in the mouse L4 and L5 dorsal root ganglion following unilateral sciatic nerve transection. The timepoint of 7 days post-axotomy was chosen to capture miRNA expression profiles at a time when the injured neurons were beginning to regenerate. Two condition experiment, paired control DRG vs axotomised DRG following unilateral sciatic nerve transection. 3 biological replicates, one replicate per array. Dye swap in Replicate 2.
Project description:Sciatic nerve ligation was performed on cohorts of 2-month and 24-month old animals. Resulting gene-expression data were generated from sciatic nerve 1 and 4 days after injury compared to naïve animals. Results show differences in sciatic nerve responses with normal aging. Total RNA taken from sciatic nerves from 2-month and 24-month old animals at either day 0, 1 and 4 after sciatic nerve crush injury.
Project description:To elucidate transcriptional responses in peripherally injured neurons, we performed RNA-seq of dorsal root gangliona (DRG) sensory neurons at 1 and 5 days following sciatic nerve injury.
Project description:Analysis of gene expression in injured primary DRG with or without camptothecin (CPT) treatment after sciatic nerve crushing may help us identify critical molecular pathways related to axon regeneration. We performed RNA-sequencing of (i) Naive primary DRG tissues without injury, (ii) Primary DRG tissues with vehicle treatment different time-points (18, 24, 36 hours) after sciatic nerve injury, and (iii) Primary DRG tissues with camptothecin treatment different time-points (18, 24, 36 hours) after sciatic nerve injury.
Project description:Here, we established a rat sciatic nerve injury model and investigated the circRNA expression profiles by Next-generation sequencing. In all, 7222 distinct circRNA candidates were found in these tissues and 4942 of these circRNAs contained at least two unique back-spliced reads. On the basis of expression of circRNA analysis, we found 131 circRNAs to be significantly (p-value<=0.05, Fold-change>=2) differently expressed in injured sciatic nerve tissues compared with matched normal tissues. All these circRNAs are derived from 21 rat chromosomes.
Project description:Sciatic nerve crush (SNC) triggers sterile inflammation within the distal nerve and deafferented dorsal root ganglia (DRGs). Granulocytes and pro-inflammatory Ly6Chigh monocytes infiltrate the nerve first, and rapidly give way to Ly6C- inflammation-resolving macrophages. Inflammation in DRGs is dominated by tissue resident macrophages, with little contribution from hematogenous leukocytes. Single-cell transcriptomics analysis of injured nerve identified six macrophage subpopulations, repair Schwann cells, and mesenchymal cells as the main cell types. Macrophages at the nerve crush site are distinct from macrophages associated with degenerating nerve fibers. Monocytes and macrophages in the injured nerve “eat” cell corpses of apoptotic leukocytes and thereby promote an anti-inflammatory milieu. Myeloid cells in the injured nerve, but not DRGs, strongly express the receptor for the chemokine GM-CSF. In the absence of GM-CSF, conditioning-lesion induced regeneration of DRG neuron central projections is abolished. Thus, a carefully orchestrated immune response in the nerve is required for conditioning-lesion induced neurorepair.