Correlation between serum microRNA-136 levels and RAAS biochemical markers in patients with essential hypertension.

The aim of this study was to investigate the correlation between microRNA-136 levels and biochemical markers of renin-angiotensin-aldosterone system (RAAS) in patients with essential hypertension (EH). The subjects were divided into EH group (n=110) and healthy control group (n=110). MicroRNA-136 expression, angiotensin-converting enzyme (ACE) activity, and expression of renin (RA) and angiotensin II (Ang II), and aldosterone (ALD) in peripheral blood serum were examined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), equine glycylglycine glycine method, magnetic particle chemistry, and radioimmunoassay, respectively. In addition, the correlation between microRNA-136 and RAAS biochemical markers was estimated by Pearson linear regression. Meanwhile, ROC curve analysis was carried out to evaluate the potential of microRNA-136 for the diagnosis of EH. Follow-up data were recorded for assessing the influence of microRNA-136 on the prognosis in patients with EH. It was found that microRNA-136 expression was remarkably elevated in peripheral blood serum of patients with EH, and the expression levels of biochemical markers of RASS, such as ACE, RA, Ang II, and ALD were also found higher than those in healthy controls. Meanwhile, a significant positive correlation was confirmed between microRNA-136 level and ACE activity, RA, Ang II, as well as ALD levels in patients with EH. In addition, the area under the ROC curve (AUC) was calculated as 0.8662, with a sensitivity of 82.73% and a specificity of 80.91%. After two-months medication intervention, patients with EH expressing a high level of microRNA-136 had better therapeutic efficacy than those with a low level. In peripheral blood serum, microRNA-136 expression was dramatically negatively correlated with biochemical markers of RASS. High level of microRNA-136 predicts a good prognosis in patients with EH following medication. Therefore, microRNA-136 can be used as a potential biomarker for the diagnosis of EH.