[Expressions and neural function prognostic evaluation of serum microRNA-24 and microRNA-29b in elderly patients with acute ischemic stroke].

OBJECTIVE To investigate the expressions of serum microRNA-24 (miR-24) and microRNA-29b (miR-29b) in elderly patients with acute ischemic stroke (AIS) and their neural function prognostic value. METHODS A prospective study was conducted. 170 elderly patients with AIS admitted to department of neurology of Danzhou People's Hospital from January 1st, 2017 to March 31st, 2019 were enrolled. According to modified Rankin scale (mRS) score, the patients were divided into good neural function prognosis group (mRS score ≤ 2, n = 105) and poor neural function prognosis group (mRS score > 2, n = 65). According to National Institutes of Health stroke scale (NIHSS) score, the patients were divided into mild group (NIHSS score < 5, n = 50), moderate group (NIHSS score 5-20, n = 76) and severe group (NIHSS score > 20, n = 44). Sixty-five healthy volunteers in the same period were enrolled as the control group. The expressions of serum miR-24 and miR-29b were determined by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-qPCR). Receiver operating characteristic (ROC) curve was plotted to analyze the value of serum expressions of miR-24 and miR-29b for predicting the poor neural function prognosis of elderly patients with AIS. Pearson correlation was used to analyze the correlation between the expressions of serum miR-24, miR-29b and NIHSS, mRS scores in elderly patients with AIS. RESULTS The expressions of serum miR-24 and miR-29b in the AIS group were significantly lower than those in the healthy control group [miR-24 (2-ΔΔCt): 0.64±0.17 vs. 2.18±0.85, miR-29b (2-ΔΔCt): 0.72±0.21 vs. 3.05±0.96, both P < 0.01]. The expressions of serum miR-24 and miR-29b in the poor neural function prognosis group were significantly lower than those in the good neural function prognosis group [miR-24 (2-ΔΔCt): 0.20±0.05 vs. 1.16±0.48, miR-29b (2-ΔΔCt): 0.18±0.03 vs. 1.41±0.56, both P < 0.01]. The expressions of serum miR-24 and miR-29b in the severe group were significantly lower than those in the mild and moderate groups [miR-24 (2-ΔΔCt): 0.13±0.02 vs. 1.30±0.51, 0.56±0.14; miR-29b (2-ΔΔCt): 0.09±0.01 vs. 1.52±0.60, 0.62±0.13; all P < 0.01], and they were significantly lower in the moderate group than those in the mild group (all P < 0.01). ROC curve analysis showed that the optimal cut-off values of serum miR-24 and miR-29b expressions for predicting poor neural function prognosis in elderly AIS patients were 0.53 and 0.48, respectively. The area under ROC curve (AUC) of the two combined prognoses was 0.920 [95% confidence interval (95%CI) was 0.861-0.982], and it was significantly higher than that of miR-24 (AUC was 0.802, 95%CI was 0.742-0.860) or miR-29b (AUC was 0.835, 95%CI was 0.778-0.890) alone (Z values were 6.513 and 4.902, respectively, both P < 0.05), with sensitivity and specificity of 92.0% and 85.7%. Pearson correlation analysis showed that the expressions of serum miR-24 and miR-29b were negatively correlated with NIHSS score (r values were -0.758 and -0.794, respectively) and mRS score (r values were -0.817 and -0.860, respectively) in elderly AIS patients (all P < 0.01). CONCLUSIONS The down-regulated expressions of serum miR-24 and miR-29b are correlated with the severity degree of neurological impairment and neural function prognosis of elderly AIS patients, and the two combined have certain value for predicting the neural function prognosis of elderly AIS patients.