Objectives: Intracerebral hemorrhage (ICH) represents a serious central nervous system emergency with high morbidity and mortality, and the basal ganglia is the most commonly affected brain region. Differentially expressed microRNAs (miRs) have recently been highlighted to serve as potential diagnostic biomarkers and therapeutic targets for ICH. This study investigated the mechanism of miR-124-3p in microglial secondary inflammation after ICH.Methods: In this study, 48 patients with primary basal ganglia ICH and 48 healthy volunteers were selected and venous blood was collected from all patients on the second morning of admission (within 24 h of stroke onset). The expression of miR-124-3p in serum was detected by RT-qPCR. Three months after ICH, the patients were assessed by modified Rankin Scale (mRS), and the correlation between miR-124-3p expression and mRS score was analyzed by Pearson. The inflammatory response of microglia was induced by lipopolysaccharide (LPS) to establish the cell model of microglial inflammation. miR-124-3p expression patterns were detected in the serum of ICH patients and healthy volunteers, normal microglia, and LPS-induced microglia. The miR-124-3p mimic was transfected into LPS-induced microglia, followed by measurement of the inflammatory factors, apoptosis rate, and cell viability. The target gene of miR-124-3p was predicted and verified. The expression patterns of tumor necrosis factor receptor-associated factor 6 (TRAF6) were detected. pcDNA3.1 and pcDNA3.1-TRAF6 were transfected into LPS-induced HMC3 cells, and nucleotide-binding oligomerization domain-like receptor (NLR) pyrin domain-containing 3 (NLRP3) expression patterns were determined. Lastly, the effects of TRAF6 overexpression on apoptosis, cell viability, and inflammation in HMC3 cells were measured.Results: miR-124-3p was downregulated in the serum of basal ganglia ICH patients and LPS-induced microglia, and miR-124-3p expression was negatively correlated with mRS. Overexpression of miR-124-3p reduced the inflammatory factors and apoptosis rate and promoted cell activity in LPS-induced microglia. miR-124-3p was found to target TRAF6. Overexpression of TRAF6 enhanced the expression of NLRP3 inflammasome, inflammatory factors and apoptosis rate, and reduced cell viability.Conclusion: Our findings indicate that miR-124-3p repressed the activation of NLRP3 inflammasome by targeting TRAF6, thus inhibiting microglial secondary inflammation after ICH in basal ganglia.

Cerebral ischemia/reperfusion (I/R) injury results in detrimental complications. However, little is known about the underlying molecular mechanisms involved in the reperfusion stage. The aim of the present study was to identify a gene expression profile associated with cerebral ischemia/reperfusion injury. The GSE23160 dataset, which comprised data from sham control samples and post-I/R injury brain tissues that were obtained using a middle cerebral artery occlusion (MCAO) model at 2, 8 and 24 h post-reperfusion, was downloaded from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) in the MCAO samples compared with controls were screened using the GEO2R web tool. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis for DEGs was performed using the online tool DAVID. Furthermore, a protein-protein interaction (PPI) network was constructed using the STRING database and Cytoscape software. In total, 32 DEGs at 2 h post-reperfusion, 39 DEGs at 8 h post-reperfusion and 91 DEGs at 24 h post-reperfusion were identified, while 15 DEGs were common among all three groups. GO analysis revealed that the DEGs at all three time-points were enriched in ‘chemotaxis’ and ‘inflammatory response’ terms, while KEGG pathway analysis demonstrated that DEGs were significantly enriched in the ‘chemokine signaling pathway’. Furthermore, following PPI network construction, Cxcl1 was identified as the only hub gene that was common among all three time-points. In conclusion, the present study has demonstrated a global view of the potential molecular differences following cerebral I/R injury and may contribute to an improved understanding of the reperfusion stage, which may ultimately aid in the development of future clinical strategies.