BACKGROUND
MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression and have emerged as potential biomarkers of cardiovascular and renal diseases. Resistant arterial hypertension (RAH) is frequently associated with chronic kidney disease (CKD) and microalbuminuria, reflecting early microvascular damage. However, the relationship between microRNA expression and microalbuminuria in patients with RAH remains insufficiently researched. This study aimed to evaluate the expression of selected miRNAs in patients with RAH, with and without CKD, and to assess their association with urinary albumin excretion.
MATERIAL AND METHODS
This cross-sectional study included 115 patients with RAH, of whom 42 (36.5%) had coexisting CKD. The expression levels of 11 selected miRNAs were assessed in peripheral blood mononuclear cells using quantitative real-time polymerase chain reaction. Urinary albumin-to-creatinine ratio (UACR) was used to assess albuminuria. Correlations between microRNA expression and UACR were analyzed using Spearman’s rank correlation.
RESULTS
In patients with RAH and microalbuminuria, a statistically significant positive correlation was observed between hsa-miR-133a expression and UACR (Spearman’s r=0.38, P=0.024, n=35). No significant correlations were found between urinary albumin excretion and other analyzed microRNAs or in patients without microalbuminuria.
CONCLUSIONS
Expression of hsa-miR-133a was associated with urinary albumin excretion in patients with RAH and microalbuminuria. The findings suggest that hsa-miR-133a may be a potential noninvasive biomarker of microalbuminuria and early renal microvascular injury in a high-risk hypertensive population; however, further longitudinal studies are required to clarify the prognostic value and clinical utility of miR-133a in this patient population.

Keywords: Hypertension; MicroRNAs; Kidney Failure, Chronic