Identifying potential therapeutic targets for ischemic stroke through immune infiltration analysis and construction of a programmed cell death­related ceRNA network.

The present study aimed to uncover the underlying mechanisms and potential intervention targets of ischemic stroke (IS). An immune cell infiltration analysis using CIBERSORT was performed on two stroke-related datasets from the Gene Expression Omnibus database to generate a competitive endogenous RNA (ceRNA) network. Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to predict potential biological functions of the network. Differentially expressed genes in the ceRNA network and programmed cell death-related genes were intersected to obtain common genes for a stroke ceRNA network related to programmed cell death. These genes were further verified through a middle cerebral artery occlusion rat model using reverse transcription-quantitative PCR. This built a ceRNA regulatory network based on bioinformatic analysis. In addition to the biological functions extracted from the GO and KEGG enrichment analyses, it was discovered that long non-coding (lnc)RNA-mediated ceRNA regulatory pathways were associated with programmed cell death. This included five for apoptosis (lncRNA deleted in lymphocytic leukemia 2 like (DLEU2L)/micro (miR)-4500/sulfite oxidase, lncRNA DLEU2L/miR-4500/transforming growth factor ß receptor III, lncRNA DLEU2L/miR-4500/BTB and CNC homology 1 (BACH1), lncRNA DLEU2L/miR-4500/zinc finger and BTB domain containing 5 and lncRNA LINC00266-1/miR-363-3p/zinc finger protein 354B and two for ferroptosis (lncRNA DLEU2L/miR-4500/ribo-nucleotide reductase regulatory subunit M2 and lncRNA DLEU2L/miR-4500/BACH1). Based on the aforementioned results, the present study provided potential approaches for bridging programmed cell death, immune infiltration and ceRNA regulatory networks in IS. The present study may provide novel insights into the clinical diagnosis and treatment of IS, and may improve the knowledge of the regulation of pathophysiological processes for IS.

Treadmill Training Reduces Cerebral Ischemia-Reperfusion Injury by Inhibiting Ferroptosis through Activation of SLC7A11/GPX4.

The mechanism by which exercise training attenuates cerebral ischemia/reperfusion (I/R) injury, especially in the regulation of iron level in neuronal damage, has not been systematically studied. Here, we showed that treadmill training inhibited ferroptosis after I/R injury in rats. Modified neurologic severity score (mNSS) test showed that the motor function, reflex, and balance abilities in the I/R injury rats after treadmill intervention were significantly improved. Treadmill training decreased the level of lipid peroxides in the cerebral cortex of ischemic rats. We found that the protein levels of ferroptosis-related proteins including nuclear transcription factor E2-related factor 2 (Nrf2), cystine/glutamate reverse transporter (SLC7A11), and glutathione peroxidase 4 (GPx4) were decreased in rats after cerebral I/R injury, while treadmill training prevented the reduction of these proteins. Furthermore, we demonstrated that erastin- (a ferroptosis activator-) induced downregulation of SLC7A11 reversed the neuroprotective effect of treadmill training. This study provides the first evidence suggesting that treadmill training suppresses ferroptosis by activating the SLC7A11/GPx4 pathway, thereby protecting against cerebral I/R injury.

Bioinformatics Analysis Identifies Potential Ferroptosis Key Genes in the Pathogenesis of Intracerebral Hemorrhage.

Intracerebral hemorrhage (ICH) is a dangerous neurological disease. The mechanism of ferroptosis in ICH remains unclear. Using bioinformatics analysis, we aimed to identify the key molecules involved in ferroptosis and provide treatment targets for ICH to further explore the mechanism of ferroptosis in ICH. GSE24265 was downloaded from the Gene Expression Omnibus (GEO) dataset and intersected with ferroptosis genes. A total of 45 differentially expressed genes (DEGs) were selected, most of which were involved in the TNF signaling pathway and oxidative stress response. Key modules constructed by the protein-protein interaction (PPI) network analysis and screening of genes related to the TNF signaling pathway led to the confirmation of the following genes of interest: MAPK1, MAPK8, TNFAIP3, ATF4, and SLC2A1. Moreover, MAPK1 was one of the key genes related to TNF signaling and oxidative stress, and it may play an important role in ferroptosis after cerebral hemorrhage. The MAPK1-related molecules included hsa-miR-15b-5P, hsa-miR-93-5P, miR-20b-5p, SNHG16, XIST, AC084219.4, RP11-379K17.11, CTC-444N24.11, GS1-358P8.4, CTB-89H12.4, RP4-773N10.5, and FGD5-AS1. We also generated a hemorrhage rat model, which was used to conduct exercise intervention in ICH rats, and qRT-PCR was used to assess the expression levels of our genes of interest. The mRNA levels after cerebral hemorrhage showed that MAPK1, ATF4, SLC2A1, and TNFAIP3 were upregulated, whereas MAPK8 was downregulated. Treadmill training increased the expression of anti-inflammatory molecules TNFAIP3 and SLC2A1 and reduced the expression of MAPK1, ATF4, and MAPK8, indicating that treadmill training may be utilized as antioxidant therapy to decrease neuronal ferroptosis. The results of this study indicated that the MAPK1-related mRNA-miRNA-lncRNA interaction chain could be potentially employed as a biomarker of the inception and progression of ferroptosis after cerebral hemorrhage.