Plasma let-7i and miR-15a expression are associated with the effect of recombinant tissue plasminogen activator treatment in acute ischemic stroke patients

Abstract

Circulating microRNAs (miRNAs) have been reported as diagnosis biomarkers and predictors in acute ischemic stroke (AIS). However, how the expression of circulating miRNAs changes after recombinant tissue plasminogen activator (rt-PA) treatment in AIS patients is still unknown. ObjectiveTo determine the expression of circulating miRNAs in AIS patients receiving rt-PA treatment and those not receiving it. MethodsBlood samples were collected 24h after onset from 40 AIS patients receiving rt-PA treatment and 46 AIS patients (admission at 8–24h of onset) not receiving rt-PA treatment. Thirty-nine age- and sex-matched healthy volunteers were used as the control group. We used miRNA microarrays to detect plasma miRNA expression and real-time PCR to verify miRNA expression. ResultsCompared to the non–rt-PA treatment group, the rt-PA treatment group showed 16 differentially expressed miRNAs. The change in the expression of let-7i and miR-15a was confirmed by real-time PCR. Compared to the heathy controls, the non–rt-PA group showed decreased let-7i expression and the rt-PA group showed a 4-fold increased let-7i expression. The let-7i expression was also found to correlate with the National Institute of Health stroke scale (NIHSS) score (rho=0.297, P=0.005). On the contrary, miR-15a expression decreased by 0.5-fold in the rt-PA group compared to that in the non-rt-PA group. ConclusionThe circulating miRNAs let-7i and miR-15a showed differential expression between AIS patients receiving thrombolysis treatment (rt-PA group) and those not receiving it (non-rt-PA group). Compared to the non-rt-PA group, the rt-PA group showed upregulation of let-7i and downregulation of miR-15a.