Lower mir-126 plasma concentrations in human pulmonary arterial hypertension

Objective: Pulmonary arterial hypertension (PAH) is a fatal incurable disease with complicated and lengthy diagnosis. However, its early detection is a prerequisite for better treatment and longer survival of patients. Therefore, the goal is not only to find new treatment procedures, but also ways to diagnose PAH faster and easier by biomarkers specifically involved in disease progression. Tissues of the cardiovascular system produce, among others, hsa-mir-126-3p (endothelium) and hsa-mir-423-5p (cardiac muscle). These microRNAs are specific for these tissues and therefore we expect a change in their concentration in patients with PAH. The choice of these molecules was conditioned by a literature search and their sufficient occurrence in human plasma. Design and method: MicroRNAs were obtained from the plasma of patients (n = 29) undergoing right ventricular catheterization with observed suspected deteriorated heart conditions in a specialized center (NÚSCH a.s). The samples were processed by modified isolation of nucleic acids using Trizol reagent, transcribed into a DNA sequence by reverse transcription and their expression was determined by PCR reaction. Results: In our research, we observed in the plasma of patients with pulmonary hypertension (n = 18, mPAP = 34.61 ± 1.75, PAWP = 22.49 ± 1.72, PVR = 3.21 ± 0.26) and PAH (n = 11, mPAP = 43.73 ± 3.21, PAWP = 9.04 ± 1.04, PVR = 8.29 ± 1.55) a trend of decrease in hsa-mir-423-5p and a statistically significant decrease in hsa-mir-126-3p (p = 0.0188) in patients with PAH. Conclusions: The results may indicate that change in expression may be caused by dysregulation of endothelial cells in patients suffering from PAH.