Background: Atherosclerosis is a progressive inflammatory disease and is the main underlying mechanism of coronary artery disease (CAD). Immune system cells and cytokines play pivotal roles in the development of atherosclerosis. Several studies have shown the role of microRNA in the inflammatory processes of atherosclerosis, and miR-342-5p has been shown to be involved in macrophage activation during atherosclerosis and cytokine secretion. But until now, there has been no data regarding the association of miR-342-5p with CAD and inflammatory cytokines.
Methods: This case control study was conducted on 82 CAD patients and 80 controls. Peripheral blood mononuclear cell (PBMC) miR-342-5p expression and gene expression of IL-6 and TNF-alpha were evaluated using real time-PCR. Also, the serum levels of IL-6 and TNF-alpha were measured using ELISA kits.
Results: The results demonstrated a higher expression of miR-342-5p in CAD patients compared to controls (p < 0.001). Moreover, logistic regression revealed an increased risk of CAD according to the expression of miR342-5p after adjusting for CAD risk factors (OR [CI] =6.1 [1.0 - 37.2], p = 0.048). Also, serum IL-6 and TNF-alpha showed higher levels in CAD patients (p = 0.003 and p = 0.004, respectively). Furthermore, there were positive correlations of miR-342-5p with gene expressions and serum levels of IL-6 and TNF-alpha.
Conclusions: The present study demonstrated higher levels of miR-342-5p in CAD patients and showed positive correlation with inflammatory cytokines. This result is in accordance with a previous study, and suggested a regulatory role for miR-342-5p in atherosclerosis and cytokine secretion, although more studies are required in this direction