Identification of novel endogenous control miRNAs in heart failure for normalization of qPCR data.

MicroRNAs (miRNAs), a class of non-coding RNAs, are utilized as biomarkers for a wide range of disorders. Circulating miRNAs are proposed as potential markers in the clinical identification of heart failure (HF). However, identifying miRNA biomarkers in HF requires identification of robust endogenous control miRNAs for normalization in differential expression analysis. Hence, this study aimed to identify circulating miRNAs that can be utilized as endogenous controls in HF. We evaluated the expression of eight miRNAs, which were previously reported as endogenous controls in different pathological conditions. Total RNA, including miRNA, was extracted from the serum samples of 30 HF patients (15 HFrEF and 15 HFpEF) and their matched controls (n = 15). We used quantitative PCR to determine the miRNA expression. The stability of the selected endogenous miRNAs was assessed and compared using a standard set of criteria with the RefFinder software. Six of the eight miRNAs analyzed showed consistent expression among all sample groups. Stability analysis ranked hsa-let-7i-5p, hsa-miR-148b-3p, and hsa-miR-484 as the most stable miRNAs, indicating their potential as reliable endogenous controls.