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Background and Purpose: MicroRNAs (miRNAs) are a class of endogenous small non-coding ribonucleic acids that regulate gene expression and can impact cellular function by suppressing or activating downstream mRNA targets. Pre-clinical studies in animal models of stroke have demonstrated specific changes in miRNA expression profiles after ischemic stroke.Methods: Patients admitted to Hartford Hospital from January 2011 - March 2014 were considered for this study. Blood samples were collected within 24 hours of stroke presentation. miRNA profiles from peripheral blood samples of ischemic stroke patients were compared to controls. Patients with acute middle cerebral artery (MCA) cardioembolic strokes (based on TOAST criteria) were included (n=16). Blood collected from patients with no acute neurological deficits in an outpatient setting served as controls (n=8). Individuals with a history of active cancer, neoplastic brain lesions or traumatic brain injury were excluded. Based on literature review, 173 miRNAs were selected to assess for differential expression between cases and controls. miRNA profiling was conducted at Exiqon Services, Denmark, using miRCURY LNA™ microRNA Array. Statistical analysis was performed using SAS.Results: In patients with acute ischemic strokes, a statistically significant differential expression was observed in 14 miRNAs as compared to controls. MicroRNAs miR-1273e, miR-5187-3p were found to be downregulated in stroke patients (p=0.01). Other miRNAs showing a significant downregulation included let 7e-5p (p=0.03); miR-4709-3p, miR-4756-3p, miR-5584-3p, miR-647 (p=0.02); miR-4742-3p (p=0.03); miR-4764-5p, miR-4531 and miR-2116-5p (p=0.04). MicroRNAs miR-664a-3p (p=0.02), miR-943 (p=0.04) and miR-145-5p (p=0.03) were significantly upregulated. Differential expression in males and females was not observed.Conclusion: Ischemic stroke patients show a differential microRNA expression profile as compared to controls. Further studies can help identify microRNA signatures as well as the downstream targets involved in the ischemic stroke molecular cascade.