Circulating microRNA-21-3p in patients with arterial hypertension

Abstract

Objective — to study changes in the blood plasma levels of microRNA‑21‑3p in patients with arterial hypertension (AH) and their relationship with the characteristics of the course of the disease.
 Materials and methods. Examinations involved 24 patients with hypertension stage II and degree 2—3 (11 men, 13 women) aged from 42 to 60 years. The control group consisted of 12 practically healthy individuals, age and gender matching. The examinations were carried out in the Department of Hypertension and Kidney Diseases of the GI «L. T. Mala National Therapy Institute of NAMS of Ukraine». The degree, stage of hypertension and the presence of risk factors for cardiovascular diseases (CVD), established CVD and kidney disease were assessed in accordance with current recommendations. All patients underwent general clinical laboratory and instrumental examinations. The blood plasma level of circulating microRNA‑21‑3p was determined by quantitative reverse transcriptase‑polymerase chain reaction (qRT‑PCR) using reagent kits for monitoring and analyzing microRNA expression «TaqMan microRNA Assay» (ThermoFisher Scientific, USA). Small nuclear RNA U6 was used as a reference. Relative expression was calculated in relative units (r.u.) using the ΔΔCt method. Statistical analysis of the obtained data was carried out using standard methods with application packages Microsoft Excel and SPSS 19.0.
 Results. A significant decrease in the plasma levels of microRNA‑21‑3p in patients with hypertension was established in comparison with practically healthy individuals. The most pronounced decrease in plasma microRNA‑21‑3p levels was observed in patients with the most severe hypertension (stage 3 AH) and in subjects, in whom antihypertensive therapy did not result in the achieving target levels of «office» blood pressure (BP). Significant negative correlations were found between the plasma microRNA‑21‑3p levels and hemodynamic parameters (BP levels) and the left ventricular myocardial mass index — an indicator of the severity of left ventricular hypertrophy, one of the key lesions of target organs. The obtained results indicate the presence in patients with hypertension of a significant deficiency in the production of microRNA‑21‑3p, which, according to the literature data, has pronounced antihypertensive and cardiovascular‑ and renoprotective properties.
 Conclusions. A significant decrease in the blood plasma levels of microRNA‑21‑3p, the endogenous regulator of gene expression with antihypertensive and organoprotective properties, was established in patients with hypertension in comparison with practically healthy subjects. The revealed decrease in the blood plasma levels of this microRNA was enhanced at severe and uncontrolled hypertension and associated with the degree of hypertensive heart damage. The data obtained indicate the important role of microRNA‑21‑3p in the hypertension pathogenesis and the prospects of finding methods for correcting its production.