Background: Coronary artery disease (CAD) is the leading cause of death worldwide. Atherosclerosis, the main underlying cause of CAD, is a progressive inflammatory disease. microRNAs play a substantial role in the inflammatory process and pathogenesis of atherosclerosis. miR-155, a widely studied microRNA, is associated with inflammation but there are conflicting data regarding expression of miR-155 in CAD. miR-10a is also one of the key regulators of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway which have not been evaluated in peripheral blood mononuclear cells (PBMCs) of CAD patients.
Methods: This is a case-control study conducted on 69 angiography confirmed CAD patients and 65 controls. PBMC expressions of miR-155, miR-10a, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) were evaluated by real-time PCR in the study population. Also, serum levels of IL-6, TNF-α, interleukin-10 (IL10), and adiponectin were measured by ELISA.
Results: No significant differences in miR-155 expression was found between CAD and control group (p = 0.059), while lower expression of miR-10a was observed in CAD individuals compared to controls (p < 0.001). An independent association of miR-10a expression with risk of CAD was also demonstrated. Higher serum levels and PBMC expressions of IL-6 and TNF-α were observed in the CAD group compared to controls (p = 0.002 and p = 0.001). However, serum concentrations of IL-10 and adiponectin were lower in CAD individuals compared to controls (p < 0.001 and p = 0.005, respectively). We found a negative association of miR-10a expression with miR155, TNF-α and IL-6 gene expression as well as serum TNF-α and IL-6 levels. A positive correlation between miR10a and serum IL-10 concentrations was also shown.
Conclusions: Our findings suggested a potential role of miR-10a in the inflammatory process underlying atherosclerosis; however, more studies are needed to support these finding.