microRNA-495 alleviates endothelial cell inflammatory injury in coronary heart disease via blockade of the NF-kappa B pathway by targeting RALB

Accounting for high mortality worldwide, coronary heart disease (CHD) is a severe disease characterized by abnormal intercellular communication, and microRNAs (miRNAs or miRs) have been shown to be involved in this process. This dissertation aimed to investigate the effect of miR-495 on endothelial cell inflammatory injury in CHD by targeting Ras-like small G-protein (RALB) via the nuclear factor kappa B (NF-kappa B) pathway. A high-fat-diet-induced CHD mouse model was successfully established. Endothelial cells were isolated and treated with the miR-495 mimic, miR-495 inhibitor, siRNA-RALB, or both. Next, the relationship between miR-495 and RALB was identified using the dual-luciferase reporter assay. Tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), IL-10, and IL-1 beta levels were tested by means of enzyme-linked immunosorbent assay. Besides this, the expression of miR-495, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), RALB, NF-kappa B p65, and phosphorylated NF-kappa B p65 was determined via reverse transcription quantitative polymerase chain reaction and western blot analysis. Finally, endothelial cell proliferation, cell cycle, and apoptosis were measured. CHD mice presented with an elevated positive rate of RALB, endothelial cell apoptosis and levels of TNF-alpha, IL-6, IL-1 beta, yet a reduced IL-10 level. RALB was identified as a target of miR-495 and was downregulated by miR-495, which led to reduced expression of RALB, ICAM-1, VCAM-1, NF-kappa B p65, and phosphorylated NF-kappa B p65. miR-495 overexpression or RALB silencing decreased the levels of TNF-alpha, IL-6, and IL-1 beta, suppressed endothelial cell apoptosis and enhanced cell proliferation. In summary, miR-495 represses endothelial cell injury and inflammation through suppression of the NF-kappa B pathway by targeting RALB in CHD, suggesting that miR-495 may serve as a potential biomarker to monitor the progression to CHD.