Project description:Transcriptional changes are distinct in female and male mice in the time course of peripheral nerve injury response. Here, we present sexually dimorphic transcriptome profiles established in the space of 24 h period after sciatic nerve axotomy.
Project description:Transcriptional changes are distinct in female and male mice in the time course of peripheral nerve injury response. Here, we present sexually dimorphic transcriptome profiles established in the space of 24 h period after sciatic nerve axotomy.
Project description:Peripheral nerve injuries are common in modern society. The patients may suffer from partial or total loss of sensory, motor and autonomic function in the involved segments of the body. However, The molecular mechanisms of the regeneration program has not yet been definitively clarified and the comprehensive lncRNA expression signature in peripheral nerve regeneration remains fully unknown.We performed a high throughput microarray assay to detect lncRNA expression profile in the distal end of peripheral nerve at 0,3,7,14 day after injury.
Project description:ChIP-seq of H3K4me3 in rat peripheral nerve was used to identify transcription start sites associated with Schwann cell-expressed genes. The analysis was performed in injured and control nerve to identify injury-responsive changes in Schwann cells. H3K4me3 ChIP samples were prepared from rat sciatic nerve at 1 day post-transection using both the distal stump of the injured nerve and the contralateral (sham) nerve.
Project description:ChIP-seq of H3K27acetylation in sham and injured nerve. Schwann cells play an important role in the response of peripheral nerve to injury. This study was designed to identify enhancers that are altered in sciatic nerve at 3 days post-injury to help identify pathways that mediate the gene expression reprogramming that occurs in Schwann cells after nerve injury. We employed ChIP-seq analysis of H3K27 acetylation as a mark of actively engaged enhancers, and compared enhancers in the distal stump of transected sciatic nerve compared to contralateral (sham) condition.
Project description:Proteomic analysis of injured human peripheral nerves, particularly focusing on events occurring in the proximal and distal nerve ends, remains relatively underexplored. This study aimed to investigate the molecular patterns underlying a digital nerve injury, concentrating on differences in protein expression between the proximal and distal nerve ends. A total of 26 human injured digital nerve samples (24 men; 2 women; median age 47 [30-66] years), harvested during primary nerve repair within 48 hours post-injury from proximal and distal nerve ends, were analyzed using mass spectrometry. A total of 3914 proteins were identified, with 127 proteins showing significant differences in abundance between the proximal and the distal nerve ends. The downregulation of proteins in the distal nerve end was associated with synaptic transmission, autophagy, neurotransmitter regulation, cell adhesion and migration. Conversely, proteins upregulated in the distal nerve end were implicated in cellular stress response, neuromuscular junction stability and muscle contraction, neuronal excitability and neurotransmitter release, synaptic vesicle recycling and axon guidance and angiogenesis. Investigation of proteins, with functional annotations analysis, in proximal and the distal ends of human injured digital nerves, revealed dynamic cellular responses aimed at promoting tissue degeneration and restoration, while suppressing non-essential processes.
Project description:Wallerian degeneration (WD) involves the fragmentation of axonal segments disconnected from their cell bodies, segmentation of the myelin sheath, and removal of debris by Schwann cells and immune cells. The removal and downregulation of myelin-associated inhibitors of axonal regeneration and synthesis of growth factors by these two cell types are critical responses to successful nerve repair. Here, we analyzed the transcriptome of the sciatic nerve of mice carrying the Wallerian degeneration slow (WldS) mutant gene, a gene that confers axonal protection in the distal stump after injury, therefore causing significant delays in WD, neuroinflammation, and axonal regeneration. 56 C57BL6 mice and 56 C57BL/6 OlaHsd-Wlds mice were anesthetized with isoflurane and underwent a microcrush lesion of their left sciatic nerve at the mid-thigh level (exept naive mice, t0). At 0, 3, 7 and 14 days post-injury, mice were anesthetized and killed by cervical dislocation. Sciatic nerves were collected and conective tissue removed. A 4-mm long sciatic nerve segment was taken from the nerve distal stump, starting at 1 mm distal from the lesion up to 5 mm distal. Distal nerve stumps were pooled by group and RNA extracted. Samples were hybridized to GeneChip® Mouse Genome 430 2.0 Array (Affymetrix). Biological replicate was done.
Project description:Retrograde signaling from axon to soma activates intrinsic regeneration mechanisms in lesioned peripheral sensory neurons; however, the links between axonal injury signaling and the cell body response are not well understood. Here, we used phosphoproteomics and microarrays to implicate ~900 phosphoproteins in retrograde injury signaling in rat sciatic nerve axons in vivo and ~4500 transcripts in the in vivo response to injury in the dorsal root ganglia. Computational analyses of these data sets identified ~400 redundant axonal signaling networks connected to 39 transcription factors implicated in the sensory neuron response to axonal injury. Experimental perturbation of individual overrepresented signaling hub proteins, including Abl, AKT, p38, and protein kinase C, affected neurite outgrowth in sensory neurons. Paradoxically, however, combined perturbation of Abl together with other hub proteins had a reduced effect relative to perturbation of individual proteins. Our data indicate that nerve injury responses are controlled by multiple regulatory components, and suggest that network redundancies provide robustness to the injury response Microarrays were run on mRNA extracted from adult rat L4 and L5 DRGs cells after 1,3,8,12,16,18,24, and 28 hours after a sciatic nerve (proximal and distal) lesion.
Project description:We applied Solexa sequencing technology to identify rat microRNA genes in proximal sciatic nerve following sciatic nerve resection. Using Solexa sequencing, computational analysis and Q-PCR verification, 93 novel miRNAs in rats were discovered and identified, of which 42 novel miRNAs were first reported in proximal sciatic nerve of rat and 51 novel miRNAs were produced at days 1, 4, 7 and 14 after sciatic nerve resection. These data provide an important resource relating to the role and regulation of miRNAs for future studies relating to peripheral nerve injury and regeneration. Keywords: Small RNA sequencing 18-30 nt small RNAs from proximal sciatic nerve of 30 Thirty Sprague-Dawley (SD) rats were sequenced at one Solexa lane
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.