Stroke is one of the major causes of death and long-term disability, of which
acute ischemic stroke (AIS) is the most common type. Although
circular RNA (
circRNA) expression profiles of AIS patients have been reported to be significantly altered in blood and peripheral blood mononuclear cells, the role of exosome-containing
circRNAs after AIS is still unknown. Plasma exosomes from 10 AIS patients and 10 controls were isolated, and through microarray and bioinformatics analysis, the profile and putative function of
circRNAs in the plasma exosomes were studied. A total of 198
circRNAs were differentially quantified (|log2 fold change| ≥ 1.00, p < 0.05) between AIS patients and controls. The levels of 12 candidate
circRNAs were verified by qRT-PCR, and the quantities of 10 of these
circRNAs were consistent with the data of microarray. The functions of host genes of differentially quantified
circRNAs, including
RNA and
protein process, focal adhesion, and leukocyte transendothelial migration, were associated with the development of AIS. As a
miRNA sponge, differentially quantified
circRNAs had the potential to regulate pathways related to AIS, like PI3K-Akt, AMPK, and
chemokine pathways. Of 198 differentially quantified
circRNAs, 96
circRNAs possessing a strong translational ability could affect cellular structure and activity, like focal adhesion, tight junction, and endocytosis. Most differentially quantified
circRNAs were predicted to bind to EIF4A3 and AGO2-two
RNA-binding proteins (RBPs)-and to play a role in AIS. Moreover, four of ten
circRNAs with verified levels by qRT-PCR (hsa_circ_0112036, hsa_circ_0066867, hsa_circ_0093708, and hsa_circ_0041685) were predicted to participate in processes of AIS, including PI3K-Akt, AMPK, and
chemokine pathways as well as endocytosis, and to be potentially useful as diagnostic
biomarkers for AIS. In conclusion, plasma exosome-derived
circRNAs were significantly differentially quantified between AIS patients and controls and participated in the occurrence and progression of AIS by sponging
miRNA/RBPs or translating into
proteins, indicating that
circRNAs from plasma exosomes could be crucial molecules in the pathogenesis of AIS and promising candidates as diagnostic
biomarkers and therapeutic targets for the condition.