Integrated Analysis of Cerebrospinal Fluid‐Derived Exosomal miRNA Expression Profiles in a tMCAO Monkey Model During Stroke Progression

ABSTRACT Globally, stroke is a critical condition that can result in enduring disabilities and death. Evidence demonstrates that stroke is linked to a variety of biological processes. Nevertheless, the significance of miRNAs in the progression of stroke remains uncertain. The transient middle cerebral artery occlusion (tMCAO) method was used to construct an ischemic stroke model in rhesus monkeys. Magnetic Resonance Imaging (MRI) scanning was used to determine injury size. Electron microscopy, nanoparticle tracking analysis, and Western blot were employed to detect exosomes. R packages were employed to evaluate and analyze the sequencing data. Venn diagrams and heatmaps were developed to illustrate the differentially expressed miRNAs. The enrichment pathways were identified using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. We constructed four tMCAO monkey models and performed miRNA profiling of exosomes isolated from the cerebrospinal fluid before tMCAO (D0), 1 day after tMCAO (D1, the superacute phase), and 7 days after tMCAO (D7, acute phase). A landscape of miRNA profiling of 12 samples was analyzed. We compared the miRNA expressions and identified differentially expressed miRNAs following tMCAO. Twenty‐eight miRNAs were dysregulated in D1 compared with D0 and D7, suggesting a crucial role in acute brain injury. GO and KEGG analyses of the 28 miRNA‐targeted genes showed the importance of focal adhesion, Notch signaling, Hedgehog signaling pathway, Hippo signaling pathway, and PI3K‐AKT signaling pathway. The results show that dysregulated miRNAs contribute to the pathophysiology of the ischemic event. Our study provides novel therapeutic targets for stroke prevention and recovery.