Dataset Information

The expression profiling of the anterior cingulate cortex and hippocampus in chronic inflammatory pain mice

ABSTRACT: Chronic pain is a persistent unpleasant sensation that produces pathological synaptic plasticity in the central nervous system. Some of the studies demonstrate that the anterior cingulate cortex (ACC) is a critical area for nociceptive and chronic pain processing. Our previous study revealed that animal models of chronic pain alter excitatory and inhibitory synaptic transmission in the ACC. However, it is not clear what molecules are involved in the alterations of synaptic plasticity in the ACC of chronic pain models. To identify genes with altered expression in the ACC of a chronic pain model, whole transcriptome analysis were performed. In addition to the ACC, whole transcriptome analysis was also performed in the hippocampus, a brain region that has not been reported to be associated with chronic pain. Complete freund's adjuvant (CFA, Sigma-Aldrich, #F5881) into the left hind paw was used for induce chronic inflammatory pain in this study.

ORGANISM(S): Mus musculus

PROVIDER: GSE147216 | GEO | 2021/04/01

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Background: We have previously used the rat 4 day Complete Freund's Adjuvant (CFA) model to screen compounds with potential to reduce osteoarthritic pain. The aim of this study was to identify genes altered in this model of osteoarthritic pain and use this information to infer analgesic potential of compounds based on their own gene expression profiles using the Connectivity Map approach. Results: Using microarrays, we identified differentially expressed genes in L4 and L5 dorsal root ganglia (DRG) from rats that had received intraplantar CFA for 4 days compared to matched, untreated control animals. Analysis of these data indicated that the two groups were distinguishable by differences in genes important in immune responses, nerve growth and regeneration. This list of differentially expressed genes defined a âCFA signatureâ. We used the Connectivity Map approach to identify pharmacologic agents in the Broad Institute Build02 database that had gene expression signatures that were inversely related (ânegatively connectedâ) with our CFA signature. To test the predictive nature of the Connectivity Map methodology, we tested phenoxybenzamine (an alpha adrenergic receptor antagonist) â one of the most negatively connected compounds identified in this database - for analgesic activity in the CFA model. Our results indicate that at 10mg/kg, phenoxybenzamine demonstrated analgesia comparable to that of Naproxen in this model. Conclusion: Evaluation of phenoxybenzamine-induced analgesia in the current study lends support to the utility of the Connectivity Map approach for identifying compounds with analgesic properties in the CFA model. A naive (control) group of rats (n = 6) and a group of rats injected with CFA (n = 6) were used for gene expression profiling experiments. One animal from the control group did not yield sufficient amount of RNA for microarray and thus was omitted from further processing. In total, 5 microarrays each from the 5 animals in the control group, and 6 microarrays each from the 6 animals in the CFA group were analyzed.

Project description:Neuropathic pain is a chronic debilitating condition with a high comorbidity with depression. Clinical reports and animal studies have suggested that both the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC) are critically implicated in regulating the affective symptoms of neuropathic pain. Neuropathic pain induces long-term structural, functional and biochemical changes in both regions, which are thought to be regulated by multiple waves of gene transcription. However, the similarity and differences in the transcriptomic profiles changed by neuropathic pain between these regions are largely unknown. Furthermore, women are more susceptible to pain and depression than men. The molecular mechanisms underlying this sexual dimorphism remain to be explored. Here, we performed RNA sequencing and analyzed the transcriptomic profiles of the mPFC and ACC of female and male mice at 2 weeks after spared nerve injury (SNI), an early time point when the mice began to show mild depressive symptoms. Our results show that the SNI-induced transcriptomic changes in female and male mice are largely distinct. Interestingly, the female mice exhibit more robust transcriptomic changes in the ACC than male, whereas the opposite pattern occurs in the mPFC. Cell type enrichment analyses reveal that the differentially expressed genes involve genes enriched in both neurons and various types of glia. We further performed Gene Set Enrichment Analysis (GSEA), which reveal significant de-enrichment of myelin sheath development in both female and male mPFC after SNI. In the female ACC, gene sets for synaptic organization and mitochondria function are enriched, and gene sets for extracellular matrix are de-enriched after SNI, while such signatures are absent in male ACC. Collectively, these findings reveal sexual dimorphism at the transcriptional level induced by neuropathic pain, and provide novel therapeutic targets for chronic pain and its associated affective disorders.

Dataset Information

The expression profiling of the anterior cingulate cortex and hippocampus in chronic inflammatory pain mice

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure