Alteration in microRNA-155 level correspond to severity of coronary heart disease

Cardiovascular diseases are a consequence of genetic and epigenetic interactions. Inflammation contributes toward the initiation and progression of atherosclerotic lesions. Previous studies have shown that microRNA (miR) 155 plays a role in cardiovascular disease, including the prevention of inflammatory infiltration, regulation of autophagy, and participation of immunoreactions. However, the change of miR-155 level in the development of atherosclerosis remains to be determined. The initial objective of this study was that CHD patients would have altered serum miR-155 level. We also aim to identify whether circulating miR-155 content could be used as a predictor for severity of coronary atherosclerosis. Sample was collected from 300 CHD patients and 100 controls. Quantitative real-time PCR analysis was utilized on RNA isolated from plasma. Expression of miR-155 was identified on the basis of the quartiles of the Gensini score, and association between the microRNA and CHD was analyzed. CHD patients had higher miR-155 level in comparison to controls (p < .001), and the miRNA content significantly increased following an increasing Gensini score (p < .001). Gensini score was significantly associated with miR-155 expression (r = 0.6124, p < .001). Our findings suggest that interaction between circulating miR-155 expressions with classical risk factors of atherosclerotic lesions, and serum miR-155 content may serve as a novel biomarker for evaluating severity of CHD.