Protein expression profiling in the hippocampus after focal cerebral ischemia injury in rats

Bioinformatic analysis of key pathways and genes involved in pediatric atopic dermatitis

The initiation of atopic dermatitis (AD) typically happens very early in life, but most of our understanding of AD is derived from studies on AD patients in adult. The aim of the present study was to identify gene signature speficic to pediatric AD comapred with adult AD. The gene expression profiles of four datasets (GSE32924, GSE36842, GSE58558, and GSE107361) were downloaded from the GEO database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed, and protein–protein interaction (PPI) network was constructed by Cytoscape software. Total 654 differentially expressed genes (DEGs) (394 up-regulated and 260 down-regulated) were identified in pediatric AD samples with adult AD samples as control. The up-regulated DEGs were significantly enriched in the migration and chemotaxis of granulocyte and neutrophil, while down-regulated DEGs were significantly enriched in biological adhesion. KEGG pathway analysis showed that up-regulated DEGs participated in chemokine signaling pathway while down-regulated DEGs participated in adherens junction, focal adhesion, and regulation of actin cytoskeleton. The top 10 hub genes GAPDH, EGFR, ACTB, ESR1, CDK1, CXCL8, CD44, KRAS, PTGS2, and SMC3 were involved in chemokine signaling pathway, cytokine–cytokine receptor interaction, interleukin-17 signaling pathway, and regulation of actin cytoskeleton. In conclusion, we identified DEGs and hub genes involved in pediatric AD, which might be used as therapeutic targets and diagnostic biomarkers for pediatric AD.

Thousand and one kinase 1 protects MCAO-induced cerebral ischemic stroke in rats by decreasing apoptosis and pro-inflammatory factors

Background: Birth hypoxia causes neonatal mortality and morbidity. Hypoxia/ischemia can facilitate brain damage, causing various kinds of diseases, such as ischemic stroke. It is necessary to understand the potential underlying mechanisms of ischemic stroke. Previous studies revealed the involvement of thousand and one kinase 1 (TAOK1) in many cellular processes. Methods: Herein, middle cerebral artery (MCA) occlusion (MCAO) was performed in rats to establish ischemic stroke in the animal model, and cortical neural stem cells from rats were treated with oxygen-glucose deprivation (OGD) to induce ischemic stroke cell model. The animal model of ischemic stroke was validated by Bederson and Zea-Longa neurological deficit scores and rotarod test. TAOK1 expression was examined by quantitative real-time PCR (qRT-PCR), Western blot, and immunofluorescent staining both in vivo and in vitro. Result: Compared with sham animals, the MCAO rats showed a significant increase in the neurological scores, and obvious motor behavioral deficits. Meanwhile, there was increased apoptosis and inflammatory response in the model group. TAOK1 overexpression reversed the OGD-induced cell injury, while TAOK1 knockdown exhibited the opposing effects. On the mechanism, the OGD-induced suppression of PI3K/AKT, and activation of mitogen-activated protein kinase (MAPK) signaling pathways were abolished by TAOK1 overexpression, and aggravated by TAOK1 knockdown in vitro. Moreover, we proved that the inhibitory effect of TAOK1 on OGD-induced apoptosis was dependent on the intracellular kinase activity. Conclusion: TAOK1 protected MCAO-induced cerebral ischemic stroke by decreasing the pro-inflammatory factors and apoptosis via PI3K/AKT and MAPK signaling pathways.

MiR-370 accelerated cerebral ischemia reperfusion injury via targeting SIRT6 and regulating Nrf2/ARE signal pathway

Cerebral ischemia reperfusion (CIR) is one of the highly lethal diseases in the world. MicroRNA-370 (miR-370) exerts multiple functions in different diseases. However, further research is needed to investigate the potential role of miR-370 in CIR injury. The in vivo middle cerebral artery occlusion (MCAO) rat model and in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) SH-SY5Y cell model were successfully established to mimic CIR injury. The infarct sizes of brain tissues from rats were evaluated. The relationship between miR-370 and silencing information regulatory protein 6 (SIRT6) was confirmed by luciferase activity assay. The cell viability and apoptosis were determined by CCK-8 assay and terminal-deoxynucleoitidyl transferase mediated nick end labeling staining. In this study, miR-370 was upregulated in brain tissues of MCAO rats and knockdown of miR-370 decreased cerebral infarction volume of MCAO rats and it alleviated CIR injury in vivo. The in vitro experiments indicated that knockdown of miR-370 promoted cell viability and alleviated OGD/R-induced SH-SY5Y cell apoptosis. Additionally, the TargetScan predicted that SIRT6 was a target of miR-370 and confirmed by luciferase activity assay. Moreover, miR-370 inhibited SIRT6 expression and regulated Nrf2/ARE signal pathway, whereas overexpression of SIRT6 partly reversed the effect of miR-370 on OGD/R-induced SH-SY5Y cell injury. Thus, we could conclude that miR-370 accelerated CIR injury via targeting SIRT6 and regulating Nrf2/ARE signal pathway, which might provide novel therapeutic targets for CIR injury treatment.

Astilbin attenuates cerebral ischemia/reperfusion injury by inhibiting the TLR4/MyD88/NF-κB pathway

Ischemic stroke is the second most common cause of death worldwide and cerebral ischemia/reperfusion (I/R) injury also leads to serious tissue damage. Astilbin, a natural bioactive flavonoid compound, has been reported to have protective effects on neurological diseases. This study aims to investigate the effects of astilbin on cerebral I/R injury and determine the mechanisms involved. The results demonstrated that, in cerebral I/R rats, astilbin could attenuate I/R injury in the hippocampal region, decreasing the activity of lactate dehydrogenase (LDH) and malondialdehyde (MDA) in the rat brain. Astilbin also inhibited the I/R-induced upregulation of pro-inflammatory mediators (TNFα, IL-1β, IL-6). Similarly, in hypoxia/reperfusion (H/R) treated human neuroblastoma cells, astilbin could increase the cell viability of SH-SY5Y, decrease the activity of LDH and MDA, and inhibit the H/R-induced upregulation of pro-inflammatory mediators. For the mechanism study, western blot results indicated that astilbin could inhibit the expression of Toll-like receptor 4 (TLR4), myeloid differential protein 88 (MYD88) and phosphorylated NF-κB p65 in H/R treated SH-SY5Y cells. The research indicated that astilbin ameliorated cerebral I/R injury partly via the TLR4/MyD88/NF-κB pathway. Astilbin may have potential therapeutic effects on cerebral ischemia.