Identification of Blood Circular RNAs as the Potential Biomarkers for Acute Ischemic Stroke

Many hospitals lack facilities for accurate diagnosis of acute ischemic stroke (AIS). Circular RNA (circRNA) is highly expressed in the brain and is closely associated with stroke. In this study, we examined whether the blood-borne circRNAs can be promising candidates as adjunctive diagnostic biomarkers and their pathophysiological roles after stroke. We profiled the blood circRNA expression in mice subjected to experimental focal cerebral ischemia, and validated the selected circRNAs in AIS patients. We demonstrated that 128, 198 and 789 circRNAs were significantly altered at 5 min, 3 h and 24 h after ischemic stroke, respectively. circRNA expression in mouse blood of sham-operated group and of middle cerebral artery occlusion (MCAO)-operated groups at 5 min, 3 hr and 24 hr after MCAO surgery. Three independent experiments were performed in sham-operated group, MCAO-operated groups at 5 min, 3 hr and 24 hr.