Project description:Neuropathic pain is an apparently spontaneous experience triggered by abnormal physiology of the peripheral or central nervous system, which evolves with time. Neuropathic pain arising from peripheral nerve injury is characterized by a combination of spontaneous pain, hyperalgesia and allodynia. There is no evidence of this type of pain in human infants or rat pups; brachial plexus avulsion, which causes intense neuropathic pain in adults, is not painful when the injury is sustained at birth. Since infants are capable of nociception from before birth and display both acute and chronic inflammatory pain behaviour from an early neonatal age, it appears that the mechanisms underlying neuropathic pain are differentially regulated over a prolonged postnatal period. We used microarrays to detail the global programme of gene expression underlying the differences in nerve injury between along the postnatal development and identified distinct classes of regulated genes during the injury Experiment Overall Design: We have performed a microarray analysis of the rat L4/L5 dorsal root ganglia, 7 days post spared nerve injury, a model of neuropathic pain. Genes that are regulated in adult rats displaying neuropathic behaviour were compared to those regulated in young rats (10 days old) that did not show the same neuropathic behaviour.
Project description:This program addresses the gene signature associated with DRG in the Chung rat model for neuropathic pain. The Chung neuropathic pain profiling data was analyzed by identifying genes that were up- and down-regulated at selected p value and fold change in DRG of the Sprague Dawley rats following spinal nerve ligation compared to the sham-operated controls.
Project description:Peripheral nerve injury alters the expression of hundreds of proteins in dorsal root ganglia (DRG). Targeting some of these proteins has led to successful treatments for acute pain, but not for sustained postoperative neuropathic pain. The latter may require targeting multiple proteins. Since a single microRNA (miR) can affect the expression of multiple proteins, here, we describe an approach to identify chronic neuropathic pain-relevant miRs. We used two variants of the spared nerve injury (SNI): Sural-SNI and Tibial-SNI and found distinct pain phenotypes between the two. Both models induced strong mechanical allodynia, but only Sural-SNI rats maintained strong mechanical and cold allodynia, as previously reported. In contrast, we found that Tibial-SNI rats recovered from mechanical allodynia and never developed cold allodynia. Since both models involve nerve injury, we increased the probability of identifying differentially regulated miRs that correlated with the quality and magnitude of neuropathic pain and decreased the probability of detecting miRs that are solely involved in neuronal regeneration. We found seven such miRs in L3-L5 DRG. The expression of these miRs increased in Tibial-SNI. These miRs displayed a lower level of expression in Sural-SNI, with four having levels lower than those in sham animals. Bioinformatics analysis of how these miRs could affect the expression of some ion channels supports the view that, following a peripheral nerve injury, the increase of the 7 miRs may contribute to the recovery from neuropathic pain while the decrease of four of them may contribute to the development of chronic neuropathic pain. The approach used resulted in the identification of a small number of potentially neuropathic pain relevant miRs. Additional studies are required to investigate whether manipulating the expression of the identified miRs in primary sensory neurons can prevent or ameliorate chronic neuropathic pain following peripheral nerve injuries. To identify the miRs that were differentially dysregulated between Tibial-SNI and Sural-SNI, we first performed 12 microarrays in a limited number of samples (in four individual DRGs per group: Sham, Tibial-SNI and Sural-SNI; two L3-DRG and two L4-DRG). Then, miRs identified as having differential expression were corroborated with real time qRT-PCR in RNA isolated from individual DRGs (L3, L4 and L5) derived from 4 rats per group (not presented here, but in the manuscript).
Project description:Candida albicans is an opportunistic pathogen and responsible for candidiasis. C. albicans readily forms biofilms on various biotic and abiotic surfaces, and these biofilms can cause local and systemic infections. C. albicans biofilms are more resistant than its free yeast to antifungal agents and less affected by host immune responses. Transition of yeast cells to hyphal cells is required for biofilm formation and is believed to be a crucial virulence factor. In this study, six components of ginger were investigated for antibiofilm and antivirulence activities against a fluconazole-resistant C. albicans strain. It was found 6-gingerol, 8-gingerol, and 6-shogaol effectively inhibited biofilm formation. In particular, 6-shogaol at 10 µg/ml significantly reduced C. albicans biofilm formation but had no effect on planktonic cell growth. Also, 6-gingerol and 6-shogaol inhibited hyphal growth in embedded colonies and free-living planktonic cells, and prevented cell aggregation. Furthermore, 6-gingerol and 6-shogaol reduced C. albicans virulence in a nematode infection model without causing toxicity at the tested concentrations. Transcriptomic analysis using RNA-seq and qRT-PCR showed 6-gingerol and 6-shogaol induced several transporters (CDR1, CDR2, and RTA3), but repressed the expressions of several hypha/biofilm related genes (ECE1 and HWP1), which supported observed phenotypic changes. These results highlight the antibiofilm and antivirulence activities of the ginger components, 6-gingerol and 6-shogaol, against a drug resistant C. albicans strain.
2018-12-25 | GSE117201 | GEO
Project description:Hippocampus transcriptome of rats with comorbid diabetic neuropathic pain and depression
Project description:To investigate mechanisms underlying neuropathic pain, we established sciatic nerve chronic constriction injury (CCI) neuropathic pain model in rats, and performed RNA-seq on ipsilateral bulk L4-L6 dorsal root ganglia from CCI rats and sham rats 11 days after surgery. By comprehensive analysis, we identified several key mRNAs and miRNAs, especially those associated with inflammatory immune response, may serve as promising targets, facilitating further investigation and eventually developing better therapeutic strategies for NP.
Project description:Numerous studies have elucidated the neuroprotective effect of 6-gingerol in central nervous system diseases. However, the potential role and mechanism of 6-gingerol on early brain injury (EBI) after subarachnoid hemorrhage (SAH) remains poorly understood. Here, we report that 6-gingerol exerts a neuroprotective effect on SAH-induced EBI through the GBP2/PI3K/AKT pathway. A SAH rat model was established by injecting femoral artery blood into the cisterna magna. 6-gingerol or vehicle was injected intraperitoneally one hour post-SAH induction. We found that the neurological function score and brain edema of SAH rats were significantly improved after 6-gingerol treatment, as well as neuronal apoptosis was attenuated in SAH rats by Nissl staining assay and TUNEL assay. To further explore potential molecular mechanisms associated with 6-gingerol, RNA sequencing was implemented to investigate the differences in transcriptomes between SAH rats with and without 6-gingerol treatment; and found that the expression of guanylate-binding protein 2 (GBP2) evidently was suppressed with 6-gingerol treatment compared to vehicle group. In addition, dual immunofluorescence was also employed to investigate changes in neurons, astrocytes, and microglia after 6-gingerol treatment. The results showed that GBP2 was expressed in neurons but not astrocytes or microglia. Western blotting analysis results demonstrated that the PI3K/AKT pathway was activated in the SAH rats treated with 6-gingerol. Furthermore, recombinant GBP2 protein and LY294002 (PI3K inhibitor) treatment reversed the effects of 6-gingerol treatment in SAH rats. These results indicate that 6-gingerol suppressed the expression of GBP2 to activate the PI3K/AKT pathway, improve neurologic outcomes, reduce brain edema and neuronal apoptosis. In summary, our findings suggest that 6-gingerol could attenuate EBI post-SAH in rats, and 6-gingerol may serve as a novel candidate neuroprotective drug for SAH-induced EBI.
2022-07-26 | GSE201312 | GEO
Project description:CircRNA Sequencing of Neuropathic Pain Rats
Project description:Clinical observations indicate that vitamin D is a pain alleviating molecule. In order to unveil the molecular mechanisms at play, we performed an experimental study on rats with a neuropathic pain. After three weeks of vitamin D treatment, the cerebrum, the spinal cord and the dorsal root ganglia were collected for a transcriptomic analysis, using cDNA microarrays.