Exosomal circCNOT6L Regulates Astrocyte Apoptotic Signals Induced by Hypoxia Exposure Through miR99a-5p/SERPINE1 and Alleviates Ischemic Stroke Injury

Glial and blood-brain barrier cell-derived exosomes: Implications in stroke

Exosomes are small extracellular vesicles released by cells that play a pivotal role in intercellular communication, significantly influencing both the pathophysiology and potential treatment of ischemic stroke (IS). This review examines exosomes derived from key brain cell types, including microglia, astrocytes, oligodendrocytes, oligodendrocyte precursor cells (NG2+ cells), endothelial cells, and pericytes, emphasizing their molecular cargo and functional impact in IS. Microglia-derived exosomes regulate neuroinflammation, with M2-type exosomes exhibiting neuroprotective effects, while astrocyte-derived exosomes modulate pathways involved in pyroptosis and autophagy, influencing neuronal survival. Oligodendrocyte and NG2+ cell-derived exosomes contribute to remyelination, axonal growth, and inflammatory modulation. Endothelial and pericyte-derived exosomes play critical roles in BBB integrity, neurovascular remodeling, and drug transport across the BBB. This synthesis highlights recent advances in understanding how exosome-mediated communication impacts IS recovery and explores their translational potential for biomarker development and targeted therapies. By manipulating exosomal composition and delivery mechanisms, novel therapeutic strategies may emerge, offering hope for improved IS treatment outcomes.

Exosomes and exosomal miRNAs mediate the beneficial effects of exercise in ischemic stroke

Ischemic stroke is an acute cerebrovascular disease that is one of the leading causes of death and neurological disorders worldwide. Exosomes are a novel class of intercellular signaling regulators containing cell-specific proteins, lipids, and nucleic acids that transmit messages between cells and tissues. MicroRNAs are regulatory non-coding ribonucleic acids that are usually present in exosomes as signaling molecules. Studies have shown that exosomes and exosomal microRNAs can improve the prognosis of ischemic stroke by inhibiting the inflammatory response, reducing apoptosis, improving the imbalance of oxidative and antioxidant systems, and regulating cellular autophagy, among other processes. Previous studies have shown that exercise training can exert neuroprotective effects on ischemic stroke by promoting the release of exosomes and regulating the expression of exosomal microRNAs, which in turn regulate multiple signaling pathways. Exosomes and exosomal microRNAs may be key targets for exercise to promote cerebrovascular health. Therefore, the study of exercise-mediated exosomes and their microRNAs may provide new perspectives for exploring the mechanism of exercise intervention in the prevention and treatment of ischemic stroke.

The Evolution of Ischemia-Reperfusion Injury Research in Ischemic Stroke: Insights From a Two-Decade Bibliometric Analysis

BACKGROUND

Ischemic stroke is a complex disease with high mortality and disability rates. Ischemia-reperfusion injury is a common aftermath. There have been significant advancements in understanding ischemia-reperfusion injury in ischemic stroke over the past two decades. This study aims to evaluate the current state of ischemia-reperfusion injury in ischemic stroke through bibliometric analysis, identifying key research areas and emerging trends.

METHODS

Relevant documents in the Web of Science Core Collection, SCI-Expanded from January 1, 2003, to December 31, 2023, were downloaded on July 10, 2024. Bibliometric analysis was performed using HistCite, VOSviewer, CiteSpace, and Bibliometrics online analysis platform.

RESULTS

A total of 2179 research papers from 611 journals in 66 countries were included in this study. Among these papers, China emerged as the leading contributor of ischemia-reperfusion injury in ischemic stroke publications, with Capital Medical University standing out as the institution with the highest number of publications in this area. Y. Zhang was identified as the author with the most publications during the study period. Brain Research was found to be the most prolific journal for this research. The keywords "ferroptosis", "circular RNA", "polarization", and "fatty acid binding protein" represent the current hot spots of ischemia-reperfusion injury in ischemic stroke research.

CONCLUSION

This bibliometric analysis offers the first thorough overview of hot spots and research trends in ischemia-reperfusion injury in ischemic stroke over the previous 21 years, providing researchers with new ideas in the field. "ferroptosis", "circular RNA", "polarization", and "fatty acid binding protein" may be the focus of future studies.

Uncovering endothelial to mesenchymal transition drivers in atherosclerosis via multi-omics analysis

PURPOSE

This study aimed to identify novel candidates that regulate Endothelial to mesenchymal transition(EndMT) in atherosclerosis by integrating multi-omics data.

METHODS

The single-cell RNA sequencing (scRNA-seq) dataset GSE159677, bulk RNA-seq dataset GSE118446 and microarray dataset GSE56309 were obtained from the Gene Expression Omnibus (GEO) database. The uniform manifold approximation and projection (UMAP) were used for downscaling and cluster identification. Differentially expressed genes (DEGs) from GSE118446 and GSE56309 were analyzed using limma package. Functional enrichment analysis was applied by DAVID functional annotation tool. Quantitative real-time polymerase chain reaction (qPCR) and western blotting were used for further validation.

RESULTS

Nine endothelial cell (EC) clusters were identified in human plaques, with EC cluster 5 exhibiting an EndMT phenotype. The intersection of genes from EC cluster 5 and common DEGs in vitro EndMT models revealed seven mesenchymal candidates: PTGS2, TPM1, SERPINE1, FN1, RASD1, SEMA3C, and ESM1. Validation of these findings was carried out through qPCR analysis.

CONCLUSION

Through the integration of multi-omics data using bioinformatics methods, our study identified seven novel EndMT candidates: PTGS2, TPM1, SERPINE1, FN1, RASD1, SEMA3C, and ESM1.

M1 Microglia-Derived Exosomes Promote A1 Astrocyte Activation and Aggravate Ischemic Injury via circSTRN3/miR-331-5p/MAVS/NF-κB Pathway

Background

After ischemic stroke (IS), microglia and astrocytes undergo polarization, transforming into a pro-inflammatory phenotype (M1 or A1). According to previous studies, exosomes might play an important role in the interplay between M1 microglia and A1 astrocytes after IS.

Methods

We used the microglial oxygen-glucose deprivation/reperfusion (OGD/R) model and ultracentrifugation to extract M1 microglial exosomes (M1-exos). Subsequently, we identified circSTRN3 enriched in exosomes through RNA sequencing and detected the role of circSTRN3 in astrocyte activation based on bioinformatics analysis, immunofluorescence, Western blotting, and polymerase chain reaction analysis. We validated these findings in the middle cerebral artery occlusion/reperfusion (MCAO/R) model of adult male C57BL/6J mice. Finally, we confirmed the correlation among circSTRN3, miR-331-5p, and stroke severity score in exosomes isolated from peripheral blood of IS patients.

Results

Our findings revealed that M1-exos promoted A1 astrocyte activation. CircSTRN3 was abundant in M1-exos, which could sponge miR-331-5p to affect mitochondrial antiviral signaling protein (MAVS), activate NF-κB pathway, and participate in A1 astrocyte activation. In addition, overexpressed circSTRN3 augmented the infarct size and neurological dysfunction in MCAO/R models, while miR-331-5p mimics reversed the effect. Furthermore, circSTRN3 in IS patients was positively correlated with stroke severity score (R 2 = 0.83, P < 0.001), while miR-331-5p demonstrated a negative correlation with the same score (R 2 = 0.81, P < 0.001).

Conclusion

Taken together, our research indicated that circSTRN3 from M1-exos could promote A1 astrocyte activation and exacerbate ischemic brain injury via miR331-5p/MAVS/NF-κB axis.

Runx1 promotes neuronal injury in ischemic stroke through mediating miR-203-3p/Pde4d axis

BACKGROUND

It has been reported that Runx1 engaged in IS progression, but the detailed mechanism of Runx1 in IS is still unclear.

METHODS

Mice and HT22 cells were subjected to the process of middle cerebral artery occlusion and reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R), respectively. Infract volume was tested using TTC staining. The levels of inflammatory cytokines were investigated using ELISA assay. Cell viability was examined utilizing MTS. Apoptosis rate was evaluated using flow cytometry and TUNEL. The productions of SOD and MDA were monitored by means of commercial kits. The correlations among Runx1, miR-203-3p and Pde4d were ascertained using dual luciferase reporter gene, ChIP and RNA-RNA pull-down assays.

RESULTS

Runx1 and Pde4d were abnormally elevated, while miR-203-3p was notably declined in MCAO/R mice and OGD/R-induced HT22 cells. OGD/R treatment suppressed cell viability and facilitated cell apoptosis, inflammation and oxidative stress, which were compromised by Runx1 knockdown or miR-203-3p upregulation. Runx1 bound to miR-203-3p promoter, thus decreasing miR-203-3p expression. MiR-203-3p inhibited Pde4d expression via targeting Pde4d mRNA. Runx1 deficiency-induced protection effects on OGD/R-treated HT22 cells were offset by miR-203-3p downregulation.

CONCLUSION

Runx1 aggravated neuronal injury caused by IS through mediating miR-203-3p/Pde4d axis.

Current insights and future directions of LncRNA Morrbid in disease pathogenesis

Non-coding RNAs have emerged as important regulators of gene expression and contributors to many diseases. LncRNA Morrbid, a long non-coding RNA, has been widely studied in recent years. Current literature reports that lncRNA Morrbid is involved in various diseases such as tumors, cardiovascular diseases, inflammatory diseases and metabolic disorder. However, controversial conclusions exist in current studies. As a potential therapeutic target, it is necessary to comprehensively review the current evidence. In this work, we carefully review the literature on Morrbid and discuss each of the hot topics related to lncRNA Morrbid.

Exosomes: A Cellular Communication Medium That Has Multiple Effects On Brain Diseases

Exosomes, as membranous vesicles generated by multiple cell types and secreted to extracellular space, play a crucial role in a range of brain injury-related brain disorders by transporting diverse proteins, RNA, DNA fragments, and other functional substances. The nervous system's pathogenic mechanisms are complicated, involving pathological processes like as inflammation, apoptosis, oxidative stress, and autophagy, all of which result in blood-brain barrier damage, cognitive impairment, and even loss of normal motor function. Exosomes have been linked to the incidence and progression of brain disorders in recent research. As a result, a thorough knowledge of the interaction between exosomes and brain diseases may lead to the development of more effective therapeutic techniques that may be implemented in the clinic. The potential role of exosomes in brain diseases and the crosstalk between exosomes and other pathogenic processes were discussed in this paper. Simultaneously, we noted the delicate events in which exosomes as a media allow the brain to communicate with other tissues and organs in physiology and disease, and compiled a list of natural compounds that modulate exosomes, in order to further improve our understanding of exosomes and propose new ideas for treating brain disorders.