Determination of Early Diagnostic Biomarkers of Renal Dysfunction After Cardiopulmonary Bypass: miR-21 and miR10a Mediated Postoperative Inflammation

Abstract

Objective: Acute renal failure (ARF) prevalence is high among patients who undergo cardiopulmonary bypass (CPB), and this condition can only be diagnosed via serum creatinine level (sCr) conventionally within 48 hours. Therefore, we need early novel diagnosis biomarkers to start preventive treatment of ARF. For that reason, we aimed to analyze if plasma miR-21 derived from heart, correlates with kidney- enriched miR-10a during inflammatory IL-6, IL-1β, and TNF-α response in terms of acute renal failure 30 minutes after CPB.
 Methods: Patients (n=46, Female:8 and Male:38), aged 61.08±9.41, who underwent CPB surgery were included. Blood samples were collected during the pre – and post-CPB (30 minutes after CPB). Demographic data of all cases were collected. Quantification of expression levels of miR-21 and miR-10a was done via quantitative PCR (qPCR). Determination of plasma concentration of relevant cytokines, IL-6, IL-1β, and TNF-α was done via ELISA.
 Results: The circulating level of miR-21 during post-CPB period (-11.78±6.98) was significantly higher (p≤0.05) than pre-CPB period (-6.55±7.11), but there was no significant change (p>0.05) in the circulating level of miR-10a between pre – (-12.22±3.55) and post-CPB (-11.60±3.36) periods. When we compared the mean ΔΔCt values of miR-21 and miR-10a, downregulation was observed in the expression level of miR-10a (0.62±3.77) whilst the expression level of miR-21 (-5.22±7.25) was upregulated (p≤0.05). The levels of plasma concentration of IL-6 (2.74±2.50 ng/l) and TNF-α (83.63±9.33 ng/l) were increased during post-CPB period (both were ***p